PSII - Reading Check

If a projectile is fired straight up at a speed of 10 m/s, the total time to return to its starting position is about

2 s

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

1 s

A woman who normally weighs 400 N stands on top of a very tall ladder so she is one Earth-radius above the Earth's surface. How much would she weigh there?

100 N

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

Throw an object at an angle upward. With no gravity it will follow a straight-line path. But because of gravity, at the end of 1 s, it is

5 m below the straight line

A projectile is launched vertically at 50 m/s. If air resistance is negligible, its speed upon returning to its starting point is

50 m/s

A projectile is fired horizontally in a region of no air resistance. The projectile maintains its horizontal component of speed because it

Is not acted on by any horizontal forces

The Earlybird communication satellite hovers over the same point on Earth's equator indefinitely. This is because

Its orbital period is 24 hours

A lunar month is about 28 days. If the Moon were closer to Earth than it is now, the lunar month would be

Less than 28 days

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

Longer

Planets would crash into the Sun if it weren't for

Their tangential velocities

The amount of gravitational force that acts on the space shuttle while in orbit is

Almost as much as the shuttle's weight on the Earth's surface

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

Increase

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

Increases

The planet Jupiter is about 300 times as massive as the Earth, yet on its surface you would weigh only about 3 times as much. This is because

Jupiter's radius is 10 times the Earth's radius

The reason the Moon does not crash into Earth is that

The Moon has a sufficient tangential speed

A bullet fired horizontally hits the ground in 0.5 s. If it had been fired with twice the speed in the same direction, it would have hit the ground in

0.5 s

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

Greater the gravitational force betwen them

Consider a monkey wrench released at rest at the far edge of the solar system. Suppose that it drops to Earth by virtue of only Earth's gravity. It will strike Earth's surface with a speed of about

11 km/s

Inside a freely falling elevator, there would be no

Apparent weight for you

A bullet fired from a rifle begins to fall

As soon as it leaves the barrel

Earth satellites are typically more than 100 km high so as to be above the Earth's

Atmosphere

The space shuttle orbits at altitudes greater than 150 km so as to be above Earth's

Atmosphere

In the vacuum of outer space, there is no

Atmospheric pressure

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

Decrease to one-half your original weight

The force of gravity does work on a satellite when it is in

Elliptical orbit

Each of us weighs a tiny bit less inside the ground floor of a skyscraper than we do on the ground away from the skyscraper. The reason for this is the

Mass of the building attracts us upward slightly

A lunar month is about 28 days. If the Moon were farther from Earth than it is now, the lunar month would be

More than 28 days

An Earth satellite is in an elliptical orbit. The satellite travels fastest when it is

Nearest the Earth

The fastest moving planet in a solar system is

The planet nearest the Sun

(True or False): An Earth satellite is simply a projectile freely falling around the Earth.

True

Consider two planets in space that gravitationally attract each other. If the masses of both planets is doubled, and the distance between them is also doubled, then the force between them is - One-quarter - Four times as much - Twice as much - None of these - Half as much

None of these

What prevents satellites such as the space shuttle from falling?

Nothing, they continually fall all around the Earth

Ignoring air drag, what is the maximum speed that can be given to a horizontally moving tennis ball as it clears the net 1.25 m high to remain within the edge of the court, which is 12.0 m distant?

24.0 m/s

A satellite near the Earth makes a full circle in about an hour and a half. How long would a satellite located as far away as the Moon take to orbit the Earth?

About 28 days

The circular orbit of a satellite orbiting the Earth is characterized by a constant - Speed - All of these - Acceleration - None of these - Radial distance

All of these

Without air resistance, a projectile fired horizontally at 8 km/s from atop a mountain will - All of these - None of these - Return later to its starting position and repeat its falling behavior - Accelerate downward at g as it moves horizontally - Trace a curve that matches the Earth's curvature

All of these

It takes Pluto a longer time to travel around the Sun than the Earth does because Pluto - None of these - Goes slower - Has farther to go - Both of these

Both of these

Two motorcycle stunt drivers, one light and the other much heavier, drive their motorcycles up and off an inclined ramp at identical speeds. They both rise in the air and land downrange. Neglecting air drag, the one to attain the greatest height and greatest range is the

Both the same

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

Buy at a high altitude and sell at a low altitude

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

Decreases

Two objects move toward each other because of gravity. As the objects get closer and closer, the force between them

Increases

When the distance between two stars decreases by half, the force between them

Increases to four times as much

If your mass, the mass of the Earth, and the mass of everything in the solar system were twice as much as it is now, yet everything stayed the same size, your weight on Earth would

Quadruple

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

Remains unchanged

A projectile is fired vertically from the surface of the Earth at 8 km/s. The projectile will

Rise and fall back to Earth's surface

A ball player wishes to determine pitching speed by throwing a ball horizontally from an elevation of 5 m above the ground. The player sees the ball land 20 m down range. What is the player's pitching speed?

20 m/s

A hunter aims a rifle at an angle of 10° above the horizontal. The hunter fires a bullet while simultaneously dropping another bullet from the level of the rifle. Which bullet will hit the ground first?

The dropped one

A ball is thrown upwards and caught when it comes back down. Neglecting air resistance, the speed with which it is caught is

The same as the speed it had when thrown upwards

Passengers in a high-flying jumbo jet feel their normal weight in flight, while passengers in the orbiting space shuttle do not. This is because passengers in the space shuttle are

Without support forces