Force Questions

Which diagram represents the directions of the velocity, v, and acceleration, a, of a toy car as it moves in a clockwise, horizontal, circular path at a constant speed?

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An electron in a magnetic field travels at constant speed in the circular path represented in the diagram below. Which arrow represents the net force acting on the electron when the electron is at position A?

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The diagram below represents the forces acting on a skydiver with his parachute. The total mass of the skydiver with his parachute is 85.0 kilograms. If the magnitude of the gravitational force is 834 newtons, and the magnitude of the force of air friction is 652 newtons, the acceleration of the skydiver at the time shown is

• 2.14 m/s^2 up
• 2.14 m/s^2 down
• 7.67 m/s^2 up
• 9.81 m/s^2 down

Which object is in equilibrium?

• Earth orbiting the Sun
• a thrown baseball at its highest point above the ground
• a car moving at a constant speed in a straight line
• a bicycle skidding to a stop in a straight line

The same net force is applied to object A and object B. The mass of B is three times greater than the mass of A. Compared to the acceleration of A, the acceleration of B is

• the same
• one-third as great
• three times as great
• one- ninth as great

In an attempt to get ketchup out of a bottle, a student takes off the cap, turns the bottle upside down, accelerates it downward, and then suddenly stops it. Ketchup is released from the open bottle because the ketchup doesn’t stop moving when the bottle does. The ketchup leaving the bottle illustrates

• inertia
• resistivity
• resonance
• mass being converted to energy

A net force of one newton will

• accelerate a 1-kg mass at 1.0 m/s2
• accelerate a 1-kg mass at 9.8 m/s2
• lift a l-kg mass vertically at a constant speed of 1.0 m/s
• lift a 1-kg mass vertically at a constant speed of 9.8 m/s

The magnitude of an unbalanced force applied to a 4.0-kilogram crate is 10. newtons. If the magnitude of this applied unbalanced force is doubled, the inertia of the crate is

• halved
• unchanged
• doubled
• quadrupled

The diagram below represents two forces, F1 and F2, acting concurrently on a block sliding on a horizontal, frictionless surface. Which statement describes the motion of the block?

• The block is accelerating to the right.
• The block is accelerating to the left.
• The block is moving to the right with constant speed.
• The block is moving to the left with decreasing speed.

A 5.0-kilogram box is sliding across a level floor. The box is acted upon by a force of 27 newtons east and a frictional force of 17 newtons west. What is the magnitude of the acceleration of the box?

• 0.50 m/s2
• 2.0 m/s2
• 8.8 m/s2
• 10. m/s2