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