Force exerted on a surface by an object, equal to its weight. (Correct)
A gravitational pull experienced by objects on Earth.
Correct Answer: Force exerted on a surface by an object, equal to its weight.
2. What are the units of thrust in the SI system?
Dyne
Newton (Correct)
Pound-force
Pascal
Correct Answer: Newton
3. What is the CGS unit of thrust?
Newton
Dyne (Correct)
Pound-force
Gram-force
Correct Answer: Dyne
4. Define 1 kilogram-force (kgf) and 1 gram-force (gf) in terms of their equivalence in newtons.
1 kgf = 9.8 N, 1 gf = 0.980 dyne (Correct)
1 kgf = 10 N, 1 gf = 1 dyne
1 kgf = 9.8 N, 1 gf = 0.98 N
1 kgf = 10 N, 1 gf = 0.980 dyne
Correct Answer: 1 kgf = 9.8 N, 1 gf = 0.980 dyne
5. What is pressure, and how is it calculated?
Force per unit volume: \( P = F / V \)
Thrust per unit area: \( P = F / A \) (Correct)
Mass per unit area: \( P = M / A \)
Energy per unit area: \( P = E / A \)
Correct Answer: Thrust per unit area: \( P = F / A \)
6. Why is pressure considered a scalar quantity?
It depends on both magnitude and direction.
It depends only on magnitude. (Correct)
It has no relationship to force or area.
It is directly proportional to force in a vector form.
Correct Answer: It depends only on magnitude.
7. How does the surface area affect pressure?
Smaller surface area results in lower pressure.
Larger surface area results in higher pressure.
Smaller surface area results in higher pressure. (Correct)
Surface area does not affect pressure.
Correct Answer: Smaller surface area results in higher pressure.
8. Explain how pressure changes when a boy lies down on sand compared to when he stands on it.
Pressure increases when he lies down due to increased thrust.
Pressure decreases when he stands due to decreased thrust.
Pressure increases when he stands due to smaller surface area. (Correct)
Pressure remains constant regardless of position.
Correct Answer: Pressure increases when he stands due to smaller surface area.
9. What are the SI units of pressure?
Pascals (Pa) or \( \text{N/m}^2 \) (Correct)
Newtons (N)
Joules (J)
Dynes (dyne)
Correct Answer: Pascals (Pa) or \( \text{N/m}^2 \)
10. What is the relationship between thrust, pressure, and surface area?
Pressure is inversely proportional to both thrust and area.
Pressure is directly proportional to thrust and inversely proportional to area. (Correct)
Pressure is directly proportional to both thrust and area.
Pressure is not related to either thrust or area.
Correct Answer: Pressure is directly proportional to thrust and inversely proportional to area.
11. What are the units of pressure expressed in terms of bars and millibars?
1 bar = 100 Pa, 1 millibar = 0.01 bar
1 bar = \(10^3\) Pa, 1 millibar = 1 Pa
1 bar = \(10^5\) Pa, 1 millibar = \(10^{-3}\) bar = 100 Pa (Correct)
1 bar = \(10^6\) Pa, 1 millibar = 0.001 bar
Correct Answer: 1 bar = \(10^5\) Pa, 1 millibar = \(10^{-3}\) bar = 100 Pa
12. A brick has dimensions of \(30 \, \text{cm} \times 15 \, \text{cm} \times 10 \, \text{cm}\) and a mass of \(4.0 \, \text{kg}\). What is the thrust exerted by the brick on the ground?
39.2 Pa
39.2 N (Correct)
4.0 N
15.0 N
Correct Answer: 39.2 N
13. What is the formula used to calculate the weight of an object?
\(W = m \cdot a\)
\(W = m \cdot g\) (Correct)
\(W = m \cdot h\)
\(W = m \cdot v\)
Correct Answer: \(W = m \cdot g\)
14. In the given example, how do you calculate the pressure exerted by the brick if the side of \(30 \, \text{cm} \times 15 \, \text{cm}\) is in contact with the ground?
Convert dimensions to cm and calculate \(P = \frac{F}{A}\)
Observation: Cork floats back. Conclusion: Water exerts an upward force on the cork. (Correct)
Observation: Cork remains stationary. Conclusion: The cork’s density matches the water’s density.
Observation: Cork breaks apart. Conclusion: Water dissolves lightweight materials.
Correct Answer: Observation: Cork floats back. Conclusion: Water exerts an upward force on the cork.
96. What is the aim of Experiment 4.4?
To measure the density of water.
To understand the concept of buoyancy using a plastic bottle and water. (Correct)
To calculate the weight of water displaced by a floating object.
To measure the volume of a submerged object.
Correct Answer: To understand the concept of buoyancy using a plastic bottle and water.
97. What is the procedure for Experiment 4.4?
Submerge a metal rod in water and measure the displacement.
Press a plastic bottle into water and observe the force required to push it deeper. (Correct)
Fill a bucket with water and measure the change in volume after adding a bottle.
Attach weights to a plastic bottle and observe how it sinks.
Correct Answer: Press a plastic bottle into water and observe the force required to push it deeper.
98. What is the observation and conclusion of Experiment 4.4?
Observation: Bottle sinks completely. Conclusion: Buoyant force is insufficient.
Observation: Bottle bounces back. Conclusion: Buoyant force opposes the weight of the bottle. (Correct)
Observation: Bottle remains stationary. Conclusion: Buoyant force equals the bottle’s weight.
Observation: Bottle compresses. Conclusion: Water pressure crushes objects at depth.
Correct Answer: Observation: Bottle bounces back. Conclusion: Buoyant force opposes the weight of the bottle.
99. How does buoyant force vary with depth in Experiment 4.4?
Buoyant force decreases with depth.
Buoyant force remains constant regardless of depth.
Buoyant force increases as the bottle is pushed deeper. (Correct)
Buoyant force depends on the weight of the bottle, not depth.
Correct Answer: Buoyant force increases as the bottle is pushed deeper.
100. What do Experiments 4.3 and 4.4 demonstrate about buoyancy?
Buoyancy depends on an object’s density and volume. (Correct)
Buoyancy decreases as objects are submerged deeper.
Buoyancy is unrelated to the weight of the fluid displaced.
Buoyancy is weaker in saltwater compared to freshwater.
Correct Answer: Buoyancy depends on an object’s density and volume.
101. What is the upward force exerted by water on an object immersed in it?
Weight force.
Buoyant force or upthrust. (Correct)
Gravitational force.
Inertial force.
Correct Answer: Buoyant force or upthrust.
102. What are the SI and gravitational units of upthrust?
SI: N, Gravitational: kgf and gf. (Correct)
SI: Pa, Gravitational: dyne and N.
SI: N, Gravitational: m/s² and g.
SI: J, Gravitational: m³ and N.
Correct Answer: SI: N, Gravitational: kgf and gf.
103. What is the effect of upthrust on the weight of an object in a fluid?
It increases the object’s weight.
It reduces the apparent weight of the object. (Correct)
It balances the object’s weight, making it weightless.
It has no impact on the object’s weight.
Correct Answer: It reduces the apparent weight of the object.
104. Give examples that illustrate the effect of upthrust.
Fish floating underwater and stones being easier to lift in water. (Correct)
A person walking on sand and pulling an object in air.
Ice melting in water and gases dissolving in liquids.
Metal sinking in water and wooden blocks staying afloat.
Correct Answer: Fish floating underwater and stones being easier to lift in water.
105. What is the relationship between the volume of an immersed object and upthrust?
Upthrust is directly proportional to the object’s weight.
Upthrust increases with the volume of the object immersed. (Correct)
Upthrust remains constant irrespective of the volume immersed.
Upthrust is inversely proportional to the object’s volume.
Correct Answer: Upthrust increases with the volume of the object immersed.
106. How does the density of a fluid affect the upthrust?
Higher fluid density decreases upthrust.
Higher fluid density increases upthrust. (Correct)
Fluid density has no effect on upthrust.
Lower fluid density increases upthrust.
Correct Answer: Higher fluid density increases upthrust.
107. Is upthrust dependent on the material of the object?
Yes, upthrust depends on the object’s material.
No, upthrust depends only on the volume of the object and the fluid’s density. (Correct)
Yes, upthrust depends on the object’s shape and material.
No, upthrust depends only on the fluid’s temperature.
Correct Answer: No, upthrust depends only on the volume of the object and the fluid’s density.
108. What is the center of buoyancy?
The point where the object’s weight acts.
The point where the buoyant force acts. (Correct)
The center of mass of the object immersed in a fluid.
The average density of the displaced fluid.
Correct Answer: The point where the buoyant force acts.
109. What happens if two objects of the same volume but different materials are immersed in the same fluid?
Both experience different upthrusts due to their material difference.
Both experience the same upthrust as upthrust depends only on volume. (Correct)
The lighter material experiences higher upthrust.
The heavier material experiences lower upthrust.
Correct Answer: Both experience the same upthrust as upthrust depends only on volume.
110. In what direction does the upthrust act on an object?
Vertically downward through the center of gravity.
Horizontally toward the fluid’s surface.
Vertically upward through the center of buoyancy. (Correct)
At an angle depending on the object’s shape.
Correct Answer: Vertically upward through the center of buoyancy.
111. What factors determine whether an object floats or sinks in a fluid?
Only the object’s weight and fluid temperature.
The object’s weight and the buoyant force. (Correct)
Only the volume of the fluid displaced.
The object’s shape and the fluid’s density.
Correct Answer: The object’s weight and the buoyant force.
112. What happens if the object’s weight (\(W\)) is greater than the buoyant force (\(F_b\))?
The object floats on the fluid’s surface.
The object remains submerged without sinking or floating.
The object sinks in the fluid. (Correct)
The object rises to the surface of the fluid.
Correct Answer: The object sinks in the fluid.
113. What happens if the object’s weight (\(W\)) is equal to the buoyant force (\(F_b\))?
The object sinks to the bottom of the fluid.
The object remains fully immersed in the fluid without floating. (Correct)
The object floats partially above the fluid’s surface.
The object floats completely on the fluid’s surface.
Correct Answer: The object remains fully immersed in the fluid without floating.
114. What happens if the object’s weight (\(W\)) is less than the buoyant force (\(F_b\))?
The object sinks to the bottom of the fluid.
The object remains submerged without rising or floating.
The object rises to the surface and floats. (Correct)
The object stays stationary at the fluid’s surface.
Correct Answer: The object rises to the surface and floats.
115. What is the role of the center of buoyancy in floating or sinking objects?
It determines the weight of the object immersed in the fluid.
It acts as the point where the fluid’s weight is balanced.
It is the point through which the buoyant force acts. (Correct)
It changes the object’s density to match the fluid’s density.
Correct Answer: It is the point through which the buoyant force acts.
116. What are the three possible outcomes when an object is placed in a fluid?
The object floats, sinks, or dissolves in the fluid.
The object floats, sinks, or remains fully immersed. (Correct)
The object rotates, stays stable, or breaks apart in the fluid.
The object shrinks, expands, or remains unchanged in the fluid.
Correct Answer: The object floats, sinks, or remains fully immersed.
117. Why does a cork float on water?
Its weight is equal to the weight of water displaced.
Its weight is less than the buoyant force acting on it. (Correct)
Its density is greater than the density of water.
It is not affected by the buoyant force in water.
Correct Answer: Its weight is less than the buoyant force acting on it.
118. Why does an iron nail sink in water?
Its weight is less than the buoyant force acting on it.
Its density is greater than the density of water. (Correct)
It is not affected by water pressure at any depth.
It displaces more water than its weight.
Correct Answer: Its density is greater than the density of water.
119. What is the significance of buoyant force in floating objects?
It counteracts the object’s weight and determines whether it floats. (Correct)
It prevents objects from sinking under any circumstances.
It stabilizes the fluid’s density at different depths.
It compresses the fluid, increasing the object’s weight.
Correct Answer: It counteracts the object’s weight and determines whether it floats.
120. What is upthrust or buoyant force in a fluid?
The force exerted downward by gravity.
The force exerted upward by a fluid on an immersed object. (Correct)
The weight of the fluid displaced by the object.
The density of the fluid times the object’s mass.
Correct Answer: The force exerted upward by a fluid on an immersed object.
121. What is the cause of upthrust force in a fluid?
The gravitational pull of the Earth on the fluid.
The pressure difference between the upper and lower surfaces of the object. (Correct)
The temperature difference within the fluid.
The weight of the fluid displaced by the object.
Correct Answer: The pressure difference between the upper and lower surfaces of the object.
122. How does liquid pressure vary with depth inside a fluid?
Liquid pressure decreases with depth.
Liquid pressure increases with depth. (Correct)
Liquid pressure remains constant at all depths.
Liquid pressure depends only on the object’s weight.
Correct Answer: Liquid pressure increases with depth.
123. In which direction does upthrust act on an object immersed in a fluid?
Vertically downward through the object’s center of gravity.
Horizontally toward the surface of the fluid.
Vertically upward through the center of buoyancy. (Correct)
At an angle, depending on the object’s shape.
Correct Answer: Vertically upward through the center of buoyancy.
124. How is upthrust related to the liquid pressure on the object’s surfaces?
Upthrust is the difference between the liquid pressure on the upper and lower surfaces. (Correct)
Upthrust equals the liquid pressure on the object’s top surface.
Upthrust equals the liquid pressure on the object’s bottom surface.
Upthrust is independent of liquid pressure.
Correct Answer: Upthrust is the difference between the liquid pressure on the upper and lower surfaces.
125. What does Fig. 4.17 illustrate about upthrust?
Pressure is greater on the object’s upper face than on its lower face.
Pressure is equal on both faces of the object submerged in the liquid.
The pressure difference between the object’s faces creates an upward buoyant force. (Correct)
Upthrust is independent of the liquid’s density.
Correct Answer: The pressure difference between the object’s faces creates an upward buoyant force.
126. What is the mathematical expression for upthrust?
\( F_b = \rho g V \) (Correct)
\( F_b = \rho V h \)
\( F_b = g V h \)
\( F_b = \rho g h \)
Correct Answer: \( F_b = \rho g V \)
127. How is the upward thrust on the lower surface of an object immersed in a fluid calculated?
\( F_2 = \rho g A h_1 \)
\( F_2 = \rho g A h_2 \) (Correct)
\( F_2 = g A h_2 \)
\( F_2 = \rho A h_1 \)
Correct Answer: \( F_2 = \rho g A h_2 \)
128. How is the net upthrust on an object immersed in a fluid derived?
\( F_b = \rho g A h \) (Correct)
\( F_b = g A h \)
\( F_b = \rho g h^2 \)
\( F_b = g A h_2 \)
Correct Answer: \( F_b = \rho g A h \)
129. How is the apparent weight of an object in a fluid calculated?
\( W_{\text{apparent}} = W + F_b \)
\( W_{\text{apparent}} = W – F_b \) (Correct)
\( W_{\text{apparent}} = F_b – W \)
\( W_{\text{apparent}} = W \cdot F_b \)
Correct Answer: \( W_{\text{apparent}} = W – F_b \)
130. What does Archimedes’ principle state?
An object immersed in a fluid experiences an upward force equal to the fluid’s density.
An object immersed in a fluid experiences an upward force equal to the weight of the displaced fluid. (Correct)
An object immersed in a fluid is always lighter than its weight in air.
An object in a fluid always floats if its volume exceeds the fluid’s volume.
Correct Answer: An object immersed in a fluid experiences an upward force equal to the weight of the displaced fluid.
131. How can Archimedes’ principle be experimentally verified?
Measure an object’s weight in air and compare it to its apparent weight in water. (Correct)
Submerge an object in oil and measure the change in density.
Calculate the fluid pressure at different depths around the object.
Measure the volume of air displaced by the object in a closed container.
Correct Answer: Measure an object’s weight in air and compare it to its apparent weight in water.
132. What is the significance of the weight of displaced fluid in Archimedes’ principle?
It equals the weight of the immersed object.
It equals the apparent weight of the object.
It equals the buoyant force acting on the object. (Correct)
It exceeds the object’s weight when submerged completely.
Correct Answer: It equals the buoyant force acting on the object.
133. How is Archimedes’ principle applied in measuring the volume of an irregularly shaped object?
By measuring the weight of the object before and after immersion.
By measuring the volume of water displaced when the object is submerged. (Correct)
By calculating the pressure difference between the object’s top and bottom surfaces.
By observing whether the object floats or sinks in the fluid.
Correct Answer: By measuring the volume of water displaced when the object is submerged.
134. What is the relationship between buoyant force and displaced fluid?
Buoyant force equals the weight of the displaced fluid. (Correct)
Buoyant force equals the volume of the displaced fluid.
Buoyant force is twice the weight of the displaced fluid.
Buoyant force depends only on the object’s density, not on the fluid.
Correct Answer: Buoyant force equals the weight of the displaced fluid.
135. Why do objects appear lighter in water?
Because water absorbs some of the object’s weight.
Because the buoyant force reduces the object’s apparent weight. (Correct)
Because water exerts an equal force on all sides of the object.
Because water’s density is less than the object’s density.
Correct Answer: Because the buoyant force reduces the object’s apparent weight.
136. How can the buoyant force on an object be verified experimentally?
By measuring the weight of the object in air and in water, and the weight of displaced water. (Correct)
By calculating the object’s volume and the density of the fluid.
By observing the height of the fluid column around the object.
By measuring the time it takes for the object to float to the surface.
Correct Answer: By measuring the weight of the object in air and in water, and the weight of displaced water.
137. What is the loss in weight of an object when fully immersed in water?
Equal to the object’s actual weight.
Equal to the buoyant force. (Correct)
Equal to twice the object’s weight in air.
Equal to the fluid’s weight multiplied by its density.
Correct Answer: Equal to the buoyant force.
138. Calculate the buoyant force on an aluminum block of volume \(200 \, \text{cm}^3\) immersed in water. (Density of water = \(1000 \, \text{kg/m}^3\))
1 N
2 N (Correct)
4 N
0.5 N
Correct Answer: 2 N
139. A wooden cube of side \(10 \, \text{cm}\) floats with half its volume submerged in water. What is the upthrust acting on the cube? (Density of water = \(1000 \, \text{kg/m}^3\))
4.9 N (Correct)
9.8 N
2.45 N
0.49 N
Correct Answer: 4.9 N
140. What is the relationship between the apparent weight of an object and buoyant force?
\( W_{\text{apparent}} = W + F_b \)
\( W_{\text{apparent}} = W – F_b \) (Correct)
\( W_{\text{apparent}} = F_b – W \)
\( W_{\text{apparent}} = F_b \times W \)
Correct Answer: \( W_{\text{apparent}} = W – F_b \)
141. What is the principle of floatation?
An object floats if its weight is less than the weight of the displaced fluid. (Correct)
An object floats if its volume is greater than the fluid’s density.
An object floats if its weight is equal to the density of the fluid.
An object floats if its weight is double the displaced fluid’s weight.
Correct Answer: An object floats if its weight is less than the weight of the displaced fluid.
142. Why does a wooden block float on water?
Its density is less than the density of water. (Correct)
Its density is greater than the density of water.
Its weight exceeds the weight of the displaced water.
It does not displace any water.
Correct Answer: Its density is less than the density of water.
143. What happens when the density of an object is greater than the density of a fluid?
The object floats on the surface of the fluid.
The object sinks to the bottom. (Correct)
The object remains stationary, fully submerged.
The object dissolves in the fluid.
Correct Answer: The object sinks to the bottom.
144. What happens when the density of an object is equal to the density of a fluid?
The object sinks to the bottom of the fluid.
The object floats completely above the fluid’s surface.
The object remains fully submerged without sinking or floating. (Correct)
The object oscillates between floating and sinking.
Correct Answer: The object remains fully submerged without sinking or floating.
145. What does Fig. 4.20 illustrate about floating and sinking objects?
Sinking occurs when \(W > F_b\), and floating occurs when \(W < F_b\). (Correct)
Floating occurs when \(W = F_b\), and sinking occurs when \(W > F_b\).
All objects sink if their density exceeds the fluid’s volume.
Floating depends only on the shape of the object, not on \(W\) or \(F_b\).
Correct Answer: Sinking occurs when \(W > F_b\), and floating occurs when \(W < F_b\).
146. What is the expression for the fraction of volume immersed for a floating object?
147. How can the principle of floatation be experimentally verified?
By comparing the weight of an object with the volume of water displaced.
By measuring the displaced fluid’s weight and the object’s weight. (Correct)
By observing whether the object sinks or floats in the fluid.
By calculating the object’s density relative to the fluid.
Correct Answer: By measuring the displaced fluid’s weight and the object’s weight.
148. What fraction of an ice cube is submerged in water if the density of ice is \(920 \, \text{kg/m}^3\) and the density of water is \(1000 \, \text{kg/m}^3\)?
0.85
0.92 (Correct)
0.80
1.00
Correct Answer: 0.92
149. What fraction of a human body is immersed in mercury if the density of the body is \(7.8 \, \text{g/cm}^3\) and the density of mercury is \(13.6 \, \text{g/cm}^3\)?
0.46
0.57 (Correct)
0.64
0.70
Correct Answer: 0.57
150. Why does a loaded ship sink deeper in water compared to an unloaded ship?
It displaces less water to balance its weight.
It needs to displace more water to balance the additional weight. (Correct)
Its density increases with the added cargo.
It reduces the upthrust acting on the ship.
Correct Answer: It needs to displace more water to balance the additional weight.
151. Why does a floating ship rise slightly when entering seawater from freshwater?
Seawater is less dense than freshwater, causing the ship to rise.
Seawater is denser than freshwater, requiring less water displacement. (Correct)
The ship’s density increases in seawater.
Seawater exerts less upthrust compared to freshwater.
Correct Answer: Seawater is denser than freshwater, requiring less water displacement.
152. How does a submarine control its ability to float or sink?
By changing its weight using external anchors.
By adjusting the amount of water in its ballast tanks. (Correct)
By altering the shape of the submarine’s hull.
By increasing or decreasing its density manually.
Correct Answer: By adjusting the amount of water in its ballast tanks.
153. Why does an iceberg float on seawater?
Its density is greater than seawater.
Its density is less than seawater, causing most of it to be submerged. (Correct)
It does not displace any water.
It is not affected by buoyant forces.
Correct Answer: Its density is less than seawater, causing most of it to be submerged.
154. Why is it easier for a swimmer to float in seawater than in freshwater?
Freshwater has more upthrust compared to seawater.
Seawater has a higher density, providing greater upthrust. (Correct)
Freshwater exerts less force on submerged objects.
Seawater has less buoyant force compared to freshwater.
Correct Answer: Seawater has a higher density, providing greater upthrust.
155. What is the role of air bladders in the buoyancy of fish and whales?
To control their density by adjusting the volume of air in the bladders. (Correct)
To reduce their weight in water by releasing oxygen.
To increase their speed by reducing resistance.
To balance water pressure at different depths.
Correct Answer: To control their density by adjusting the volume of air in the bladders.
156. Why do balloons filled with hydrogen or helium float in air?
Hydrogen and helium are heavier than air.
Hydrogen and helium are lighter than air. (Correct)
The density of air is lower near the ground.
The weight of the balloon cancels out the buoyant force.
Correct Answer: Hydrogen and helium are lighter than air.
157. How do ballast tanks help in controlling the buoyancy of submarines?
By reducing the density of seawater around the submarine.
By allowing water to enter or exit, changing the submarine’s weight. (Correct)
By increasing the volume of water displaced by the submarine.
By adding more air to the interior compartments.
Correct Answer: By allowing water to enter or exit, changing the submarine’s weight.
158. Why does an ice cube float higher in seawater compared to freshwater?
Seawater has lower density, reducing the buoyant force.
Seawater has higher density, requiring less volume to be submerged. (Correct)
Freshwater provides greater upthrust than seawater.
Ice displaces more water in freshwater due to its higher temperature.
Correct Answer: Seawater has higher density, requiring less volume to be submerged.
159. Why is helium preferred over hydrogen in balloons despite hydrogen being lighter?
Helium is less expensive than hydrogen.
Helium is non-flammable, making it safer to use. (Correct)
Hydrogen exerts less buoyant force compared to helium.
Hydrogen is heavier than helium and unsuitable for floating balloons.
Correct Answer: Helium is non-flammable, making it safer to use.
160. Why do deep-sea fish have high blood pressure?
To withstand the low pressure at shallow depths.
To balance the high pressure of seawater at great depths. (Correct)
To prevent their bodies from sinking due to water pressure.
To reduce the density of their blood for better buoyancy.
Correct Answer: To balance the high pressure of seawater at great depths.
161. Why do balloons filled with hydrogen or helium float in air?
Hydrogen and helium are denser than air.
Hydrogen and helium are lighter than air. (Correct)
The density of air increases with altitude.
The weight of the balloon is greater than the buoyant force.
Correct Answer: Hydrogen and helium are lighter than air.
162. How is the relative density of a substance defined?
The ratio of the density of the substance to the density of mercury.
The ratio of the density of the substance to the density of water at \(4^\circ \text{C}\). (Correct)
The difference between the density of the substance and water.
The product of the density of the substance and water.
Correct Answer: The ratio of the density of the substance to the density of water at \(4^\circ \text{C}\).
163. What is the significance of relative density being dimensionless?
It is independent of the object’s weight.
It has no unit, as it is a ratio of two similar quantities. (Correct)
It depends on the volume of the displaced fluid.
It indicates the force exerted by the fluid on the object.
Correct Answer: It has no unit, as it is a ratio of two similar quantities.
164. What is the formula for relative density using weights?
