# Power calculations

A 50-N object falling in air experiences 30 N of air resistance. The amount of net force on the falling object is

A 10-N falling object encounters 4 N of air resistance. The net force on it is

A 20-N falling object encounters 20 N of air resistance. The net force on it is

Given that two forces of 10 N and 17 N act horizontally (one dimension) on an object, the net force must

What is the net force on a box that is being pushed to the right with 60 N of force while, at the same time, being pushed to the left with 20 N of force?

The equilibrium rule *F _{net}* = 0 applies to objects in constant motion in a straight line. This statement is

An object moving with constant speed in a straight line, or is at rest, or is in equilibrium has zero acceleration. This statement is

Whenever the net force on an object is zero, its acceleration

Burl and Paul have a total weight of 1300 N. The tensions in the ropes that support the scaffold they stand on add to 1700 N. The weight of the scaffold itself must be

The force of friction on a sliding object is 40 N. The applied force needed to maintain a constant velocity is

A bucket of cement is raised by a rope at constant speed at a construction site. Compared with the force of gravity on the bucket, the upward force supplied by the rope is

The forces acting on the object at rest are equal in magnitude and are in the same direction so that the net force is zero. This statement is

When you toss a coin straight up, it moves upward, turns around, and drops. During all this time the acceleration of the coin is

A stone is thrown vertically upward. At the top of its vertical path the force acting on it is

If you drop an object, it will accelerate downward at a rate of 10 m/s^{2}. If you instead throw it downward, its acceleration (in the absence of air resistance) will be

A constant net force on a railroad car produces constant acceleration AND constant velocity. This statement is

A 10-kg brick and a 1-kg book are dropped in a vacuum. The force of gravity on the 10-kg brick is

A 10-kg block is pushed across a friction-free horizontal surface with a horizontal force of 20 N. The acceleration of the block is

If an object falls with constant acceleration, the velocity of the object must

A force of 1 N accelerates a 1-kg mass at 1 m/s^{2}. The acceleration of a 2-kg mass acted upon by a force of 2 N is

A 1000-kg car accelerates at 2 m/s^{2}. What is the net force exerted on the car?

A ball is thrown vertically upward. At the top of its vertical path, its velocity is