26. A cart is uniformly accelerating from rest. The net force acting on the cart is a. decreasing b. zero c. constant d. increasing 27. Assume that an object has no unbalanced force acting on it. Which statement about the object is true? a. The object may be in motion b. The object must be slowing down c. The object must be at rest d. The object may be speeding up 28. If the mass of an object were doubled, it's acceleration due to gravity would be a. halved b. doubled C. unchanged d. quadrupled 29. For a freely falling object, the ratio of the force of gravity to its acceleration is a. weight b. momentum c. Kinetic energy d. mass

An object moving upward cannot be considered free-falling a.Sometimes true b.Always false c.Sometimes fals d.Always true What refers to the force perpendicular to the velocity of an object moving along a curved path?a.Centrifugal force b.Reverse-effective force c. Centripetal force d. Normal force A uniform bar of mass m is supported by a pivot at its top, about which the bar can swing like a pendulum. If a force F is applied perpendicularly to the lower end of the bar as in the diagram, how big must F be in order to hold the bar in equilibrium at an angle θ from the vertical? a.(mg/2) sin (θ)b.(mg/2) cos (θ)c.2mg cos (θ)d.mg sin (θ)e.2mg sin (θ)

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A heavy ball is thrown straight upward. After the ball leaves the thrower's hand, what forces act on the ball? a. A constant downward force from gravity, along with a steadily decreasing upward force from the thrower. b. A steadily decreasing upward force from the thrower on the way up, then a nearly constant force from gravity on the way down. c. A downward force of gravity that decreases substantially as the ball gains height, then increases substantially as the ball falls back downward. d. A steadily decreasing upward force from the thrower on the way up, then a steadily increasing force from gravity on the way down. e. A nearly constant downward force of gravity.

1. Which one of the following objects has the greatest inertia? a. ping pong ball b. a basketball c. a golf ball d. a bowling ball   2. The amount of matter in an object is called its ______.  a. inertia b. balance. c. force d. mass   no need for solutions. answer only

24. A pickup truck with mass 980 kg is initially at rest. The truck accelerates to a speed of 95 km/hr within a distance of 60 meters. What the direction and size of the force that acts on the truck? a. b. If the truck were carrying a load of 200 kg, what new force would be required to achieve the same acceleration?

2. Two masses are connected by a string, and suspended over a pulley. If one mass is 4.5 kg, and the other mass is 7.5 kg, what is the magnitude of the acceleration of the system? a. 6.1 m/s? b. 2.5 m/s² c. 3.7 m/s² d. 4.8 m/s? e. none of above

a. An object that is free-falling is acted upon by the force of gravity alone. b. A falling skydiver which has reached terminal velocity is considered to be in a state offree fall. c. A ball is thrown upwards and is rising towards its peak. As it rises upwards, it is NOT considered to be in a state offree fall d. An object in free fall experiences an acceleration which is independent of the mass of the object. e. A ball is thrown upwards, rises to its peak and eventually falls back to the original height. As the ball rises, its acceleration is upwards; as it falls, its acceleration is downwards. f. A ball is thrown upwards, rises to its peak and eventually falls back to the original height. The speed at which it is launched equals the speed at which it lands. (Assume negligible air resistance.) g. A very massive object will free fall at the same rate of acceleration as a less massive object.

A cart of mass 0.85 kg is on a track, connected by a string over a pulley to a hanging mass of 0.1 kg. A friction pad is attached to the bottom of the cart, and you push the cart so that it first moves toward the sensor, then away from the motion sensor. The net acceleration of the cart does which of the following? a. always points away feom the motion sensor b. always points toward the motion sensor c. the direction of the net acceleration cannot be determined

What happens to the object when you apply a constant force on it in space? A. It will not move B. It will continuously move C. It will move faster D. None of the above