physics chapter 4 – Flashcards

The direction of the force of friction on a sliding crate is _______.

A crate sits at rest on a factory floor. Friction between the crate and floor occurs _______.

The unit of mass is the kilogram, and the unit of weight is _______.

Which of the following depends on gravity?

In considering proportions, acceleration is _______.

When does the proportion form of Newton's second law take the form of an equation?

A 1-kg stone and a 10-kg stone have the same acceleration in free fall because _______.

As a skydiver gains speed in falling through the air, air resistance _______.

Air resistance on a parachutist at terminal speed _______.

Since an object weighs less on the surface of the Moon than on Earth's surface, does it have less inertia on the Moon's surface?

A 400 kg bear grasping a vertical tree slides down at constant velocity. What is the friction force that acts on the bear?

What weight change occurs when your mass increases by 2 kg?

A grocery bag can withstand 300 N of force before it rips apart. How many kilograms of apples can it safely hold?

Free fall is motion in which gravity is the only force acting. Is a skydiver who has reached terminal speed in free fall?

Is a satellite above the atmosphere that circles Earth in free fall?

Does a falling object increase in speed if its acceleration of fall decreases?

What is the magnitude of the net force acting on a 1-kg ball in free fall?

What is the net force acting on a falling 1-kg ball if it encounters 2 N of air resistance?

When a parachutist opens her parachute after reaching terminal speed, in what direction does she accelerate?

Which has the greater mass? an automobile battery a king-size pillow neither - both have the same

Compared to a 1-kg block of solid iron, a 2-kg block of solid iron has the same... weight. mass. volume. all of these none of these

Compared to the mass of a certain object on Earth, the mass of the same object on the moon is...

The newton is a unit of

An object's weight may properly be expressed in units of

Calculate the weight in newtons of a 2.9-kg melon. Weight = mg

Calculate the acceleration of a 2000-kg, single-engine airplane just before takeoff when the thrust of its engine is 400 N . Acceleration: a=Fnet/m

Calculate the horizontal force that must be applied to a 1.2-kg puck to make it accelerate on a horizontal friction-free air table with the same acceleration it would have if it were dropped and fell freely. Force = ma

If your friend Katelyn weighs 460 N , what is her weight in pounds?

Consider a business jet of mass 32000 kg in takeoff when the thrust for each of two engines is 24000 N . Find its acceleration.

A skydiver, who weighs 500 N, reaches terminal velocity of 90 km/h. The air resistance on the diver is then

A heavy rock and a light rock of the same size are falling through the air from a tall building. The one that encounters the greatest air resistance is the

A falling skydiver of mass 100 kg experiences 500 N of air resistance. The acceleration of the skydiver is

The human body can, under certain conditions, withstand an acceleration of 10 g. What net force would produce this acceleration of a 50-kg person?

A 2000-kg car experiences a braking force of 10,000 N and skids to a stop in 6 seconds. The speed of the car just before the brakes were applied was

A 1-kg ball is thrown at 10 m/s straight upward. Neglecting air resistance, the net force that acts on the stone when it is halfway to the top of its path is about

A block is dragged without acceleration in a straight-line path across a level surface by a force of 6 N. What is the force of friction between the block and the surface?

A push on a 1-kg brick accelerates it. Neglecting friction, to equally accelerate a 10-kg brick, one would have to push with

An object following a straight-line path at constant speed

A force of 1 N accelerates a mass of 1 kg at the rate of 1 m/s2. The acceleration of a mass of 2 kg acted upon by a net force of 2 N is

A car has a mass of 1000 kg and accelerates at 2 meters per second per second. What is the magnitude of the net force exerted on the car?

The force of friction on a sliding object is 10 newtons. The applied force needed to maintain a constant velocity is

An object is propelled along a straight-line path by a force. If the net force were doubled, the object's acceleration would be

A skydiver's terminal velocity will be greatest if she falls