Module 04 Physics

A gun with a muzzle velocity of 100 m/s is fired horizontally from a tower. Neglecting air resistance, how far downrange will the bullet be 1 s later?

100 m

If a projectile is fired straight up at a speed of 10 m/s, neglecting air resistance, the time it takes to reach the top of its path is

1s

A stone is thrown horizontally from the top of a cliff. One second after leaving your hand it drops a vertical distance of

5 m

If the radius of the Earth somehow decreased with no change in mass, your weight would

increase

Two objects move toward each other due to gravity. As the objects get closer and closer, the acceleration of each

increases

When the distance between a pair of stars decreases by half, the force between them

increases to four times as much.

Minimal orbit speed about Earth is about 8 km/s. Minimal orbital speed for a satellite about the Moon would be

less than 8 km/s.

According to Newton, the greater the distance between gravitationally interacting objects, the

less the gravitational force between them.

Why doesn't the Moon fall toward Earth like apples do?

moon does fall but due to its tangential motion it also falls around Earth

According to Newton, the closer gravitationally interacting objects are to each other, the

more the gravitational force between them

With no air resistance a projectile fired horizontally maintains its horizontal component of velocity because

no horizontal force acts on it

Gravitational force is greater for a satellite in elliptical orbit when it is at the

perigee (closest point)

The force of gravity on a bowling ball rolling along a horizontal surface doesn't change its speed because the force is

perpendicular to its direction of motion

IAs a bowling ball that rolls off the edge of a table falls, its horizontal component of motion

remains constant

Newton discovered

that gravity is universal

Occupants of the International Space Station experience weightlessness due to

the absence of a support force.

Escape speed for a rocket is less from

the moon

The fastest moving planet in a solar system is the

the planet nearest the sun

Compared to the speed a satellite loses when traveling from nearest to farthest points from Earth, the speed gained when returning from farthest to nearest is

the same

After a rock that is thrown straight up reaches the top of its path and is starting to fall back down, its acceleration is

the same as it was at the top of its path.

Escape speed for a rocket is greatest from

the sun

A projectile is launched at an angle of 15° above the horizontal and lands downrange. With no air resistance, what other projection angle for the same speed would produce the same downrange distance?

75%

Consider two planets in space that gravitationally attract each other. If the mass of one planet is doubled, and the distance between them doesn't change, then the force between them is

twice as much

Inside a freely-falling elevator you would have no

weight

Inside a freely-falling elevator your

weight is zero

An airplane flying overhead drops a care package directly over Mike at rest in his Corvette. Neglecting air resistance, the package will land

well ahead of mike and his corvette

If Earth's mass somehow doubles with no change in its size, and your mass remains the same, your weight

also doubles

If your mass doubles, your weight

also doubles

A rock is thrown upward at 50° with respect to the horizontal. As it rises, its vertical component of velocity

decreases

An object is placed exactly halfway between the Earth and the Moon. The object will fall toward the

earth

An Earth satellite in an elliptical orbit travels slowest when it is

farthest from the Earth

An Earth satellite is simply a projectile

freely falling around the earth

Compared with the period of satellites in orbit close to Earth, the period of satellites in orbit far from Earth is

greater

According to Newton, the greater the masses of interacting objects, the

greater the gravitational force between them. Submit

A woman who normally weighs 400 N stands on top of a very tall ladder so she is one Earth-radius above Earth's surface. What is her weight there?

100 N

With no air resistance, a projectile fired at 60° has the same range as if it were fired at

30°.

A projectile is launched straight upward at 50 m/s. Neglecting air resistance its speed upon returning to its starting point is

50 m/s

Communications and weather satellites always appear at the same place in the sky because these satellites are

orbiting Earth with a 24-hour period.

Escape speed from Earth is

11.2 km/s.

A ball is thrown horizontally from the top of a tall cliff. Three seconds later, the ball has fallen a vertical distance of

45 m

Phil stands at rest with both feet on a scale that reads 500 N. After he gently lifts one foot, the scale reads

500 N

As a bowling ball that rolls off the edge of a table falls, its vertical component of motion

increases

Wobbles in the path of Uranus led to the discovery of

Neptune

The planet Neptune was discovered by perturbations of

Uranus

A dropped ball gains speed because

a gravitational force acts on it.

A very massive object A and a less massive object B move toward each other under the influence of gravity. Which force, if either, is greater?

both forces on each other are the same

A hunter fires a bullet from a horizontally—held rifle while simultaneously dropping another bullet from the side of the rifle. The bullet to hit the ground first is

both hit at the same time

If the Sun were twice as massive,

both of these

A supplier wants to make a profit by buying gold by weight at one altitude and selling it at the same price per kilogram at another altitude. The supplier should

buy at a high altitude and sell at a low altitude. Submit

Acceleration is greatest for a satellite in elliptical orbit when it is

closest to earth

Without air resistance, a projectile fired horizontally at 8 km/s from a mountain top will

all of the above

You experience weightlessness

all of the above

Traveling from Earth to the Moon requires that a rocket have

any sustained speed if time isn't a factor.

A bullet fired from a rifle begins to fall

as soon as it leaves the barrel.

If Earth's mass somehow decreased with no change in its radius, your weight would

decreased also

If Earth's mass decreased to one-half its original mass with no change in radius, your weight would

decreased to one half

How far must one travel to completely be beyond Earth's gravity?

forget it; you cant travel far enough

The Moon continually falls toward Earth, but doesn't get closer because

its tangential velocity causes it to fall around as well as toward Earth. Submit

An object is thrown vertically into the air. Because of air resistance, the time for its descent will be

longer than the ascent time.

From Earth, one satellite appears to overtake another. The faster satellite that is seen to overtake the other is

lower

The tangential velocity of an Earth satellite is its velocity

parallel to the surface of earth