Science - Chapter 7.1-7.8 and 8.1-8.7

What are characteristics of projectiles?

The characteristics of an Projectiles are 1) Horizontal and Vertical components of velocity 2) Takes a shape known as Parabola 3) Under influence of gravity

A stone is thrown horizontally from the top of a cliff. One second after it has left your hand its vertical distance below the cliff is?

5 m

A person is attracted toward the center of the Earth by a 500-N gravitational force. The force of attraction of the Earth toward the person is?

500

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?

1s

If the mass of the Earth somehow increased with no change in size, your weight would?

Increase

The variable plotted on the horizontal axis (x-axis) of a graph is called the?

Independent Variable

The intensity of light decreases as distance increases. What is this rule called?

Inverse- Square Law

For Orbits of greater altitude, is the period greater or less? Why?

Its less because the farther the orbit the greater the period.

Tides in which the Earth, sun and moon are at right angles to each other and high tides are lower than average and low tides aren't as low.

Neap Tides

An Earth satellite is simply a projectile freely falling around the Earth. True or False?

True

What is Hang Time?

When your geet leave the ground for a period of time.

When does Gravitational Force get weaker?

With distance

Are the planets of the solar system simply projectiles falling around the sun?

Yes

If you mass increases does your weight increase? Why?

Yes because its directly proportional.

Do tides occur in the molten interior of the Earth for the same reason that tides occur in the oceans?

Yes same idea. The lava is effected the same way.

What do we call the gravitational force between the Earth and your body?

Your Weight

A measurement standard is defined as?

an exact quantity that people agree to use for comparison

A player catches a ball. Consider the action force to be the impact of the ball against the players glove. The reaction to this force is the?

force the glove exerts on the ball.

How far must one travel to get away from the Earths gravitational field?

forget it. You cannot escape the Earth's pull.

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

greater the gravitational force between them

A direct TV communication satellite hovers over the same point on Earths equator indefinitely. This is because?

it takes 24 hours to circle the Earth.

A light woman and a heavy man jump from an airplane at the same time and open their same-size parachutes at the same time. Which person will reach terminal velocity first?

the light woman

A sheet of paper can be withdrawn from under a container of milk without toppling it if the paper is jerked quickly. This best demonstrates that?

the milk carton has inertia

What does it mean for a Projectile to be falling around the earth?

the projectile must be moving fast enouh to match the Earth's curvature.

Compared with the mass of a certain object on Earth, the mass of the same object on the Moon is?

the same.

Planets would crash into the sun if it weren't for what?

their tangential velocities

Without air resistance, a cannonball fired horizontally at 8 km/s from atop a mountain will?

trace a curve that mathches the Earth's curvature

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

How does the brightness of a light change when a point source of light is brought twice as far away?

1/4 as bright

You make a bet with a friend that you can jump the Manistee River on your mo-ped. While this isnt a smart thing to do, what angle should you set your ramp to jump the greatest distance?

45 degrees

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

For the astronauts inside the orbiting space shuttle, there is no force of Earths gravity acting on them. This statement is?

ALWAYS FALSE

What is an Projectile?

Any object that continues in motion.

At what part of its trajectory does a projectile have minimum speed?

At the top of its path.

Why do we not see tides in lakes?

Because no part of a lake is significantly closer to the moon than any other part.

Why is their no Air Drag on the moon?

Because thier is no atmosphere on the moon.

If the size of the Earth somehow decreased with no change in mass so that you were closer to the center of the Earth, your weight would?

Decrease

If the mass of the Earth somehow doubled, and everything else remained the same, your weight would?

Double

F= g m1 m2 / d^2

F is 9.8 newtons, M, is the mass of the 1 kilogram mass and m2 is the mass of the Earth.

The Earth pulls harder on the moon than the moon pulls on the Earth. True or False

False

The escape speed from the surfaces of planets depends on the masses and sizes of the planets. True or False?

False

The gravitational field of the Earth is very weak (almost zero newtons) up there in space shuttle territory compared to down here on the Earths surface. True or False?

False

What is the difference between the big bang and the big crunch?

The difference between the big bang and the big crunch is that the big bang is the theory of the origin of the universe being created. While the Big Crunch is the theory of the Universe collapsing and another Big bang will happen.

What is centripetal?

The force that pushes an object toward the center and follow a curved path.

The Earth and moon gravitationally attract each other. Does the more massive Earth attract the moon with a greater force, the same force, or less force than the moon attracts the Earth? What reasoning guides your answer?

The more massive Earth attracts the moon with the same amount of force on the moon as the moon attracts the Earth.

What is an parabola?

The path that a projectile follows.

What causes the tides in the oceans?

Tides in the ocean are caused by differences in the gravitational pull by the moon on the earth's opposite sides.

A bullet fired from a rifle (whose barrel is level to the ground) begins to fall when?

as soon as it leaves the barrel. Correct

Earth satellites are typically more than 100 km high so as to be above the Earths?

atmosphere

A ball is batted at an angle of 30 degrees above the horizontal. Another ball is batted at 60 degrees above the horizontal at the same speed. The ball that travels farther from home plate is the one batted at

both about the same

A rock is thrown upward at 50 degrees with respect to the ground (Ignore air resistance). As it rises, its horizontal component of velocity?

remains the same

When a ball rolls off the edge of a table and falls to the floor, the horizontal component of motion?

remains the same if their is no air drag

A bullet is dropped from the top of the Empire State Building while another bullet is fired downward from the same location. Neglecting air resistance, acceleration is greatest for the?

same for each

Newton discovered what?

that gravity is universal.

What is the minimum speed, the max speed, and what happens to projectile that go above this speed?

Close Orbit- 8km/s or 18,000mph Max Speed- 25,00mph Above - It would leave the earths orbiting.

Why do satellites remain in orbit while the force of gravity pulls downward on them? Defend you answer in detail.

Satellites remain in orbit while the force of gravity pulls downward on them because their Tangential velocity allows them to stay in orbit. Because satellites have 2 ranges of speed and when they fall above those 2 ranges they fall outward of the orbit and then when they fall below those 2 ranges they go back to the earth.

Tides in which the sun, Earth, and moon line up and there are higher than average high tides and lower than average low tides.

Spring tides

A rock is thrown upward at 50 degrees with respect to the ground (ignore air resistance). As it rises, its vertical component of velocity?

decreases