Which of these things does NOT affect the amount of air drag force a falling object will experience?
Answer
A Air density
B Mass
C Speed or velocity
D surface area
Question 2
Question
Which of these objects would have the largest terminal velocity?
Answer
A bowling ball
B a feather
C an empty paper cup
D a person jumping from an airplane with a parachute deployed (open).
Question 3
Question
A stationary body floats in water.
Which statement about the forces acting on the body is correct?
Answer
A The gravitational force is equal to the viscous force.
B The gravitational force is greater than the upthrust.
C The upthrust is zero.
D The viscous force is zero.
Question 4
Question
A ball falls from rest through air and eventually reaches a constant velocity.
For this fall, forces X and Y vary with time as shown.
What are forces X and Y?
An object, immersed in a liquid in a tank, experiences an upthrust.
What is the physical reason for this upthrust?
Answer
A The density of the body differs from that of the liquid.
B The density of the liquid increases with depth.
C The pressure in the liquid increases with depth.
D The value of 'g' in the liquid increases with depth.
Question 6
Question
A ball is falling at terminal speed in still air.
The forces acting on the ball are upthrust, viscous drag and weight.
What is the order of increasing magnitude of these three forces?
Answer
A upthrust → viscous drag → weight
B viscous drag → upthrust → weight
C viscous drag → weight → upthrust
D weight → upthrust → viscous drag
Question 7
Question
A submarine is in equilibrium in a fully submerged position.
What causes the upthrust on the submarine?
Answer
A The air in the submarine is less dense than sea water.
B The sea water exerts a greater upward force on the submarine than the weight of the steel.
C The submarine displaces its own volume of sea water.
D There is a difference in water pressure acting on the top and bottom of the submarine.
Question 8
Question
The diagram represents a sphere under water. P, Q, R, and S are forces acting on the sphere, due to the pressure of the water.
Each force acts perpendicularly to the sphere’s surface. P and R act in opposite directions vertically. Q and S act in opposite directions horizontally.
Which information about the magnitudes of the forces is correct?