Chapter 3

1.

1 point

the time it takes a geosynchronous satellite to orbit the earth is

1 week

1 day

1 month

90 mins

2.

1 point

you can see where the tropopause is by

seeing how high birds fly

looking at the tops of thunderstorms

seeing where lightning comes from

looking at earth satellites

3.

1 point

At high velocities, most of the fuel used in an automobile is used to overcome

buoyancy

air resistance

momentum

gravity

4.

1 point

Compared to the weight of the payload, the fuel used in a rocket typically weighs

over 20 times more

less than half as much

about twice as much

about the same

5.

1 point

The altitude of a geosynchronous satellite is closest to

35 000 km

200 miles

600 miles

6.

1 point

The maximum acceleration of the space shuttle is about

3 g

18g

1 g

10 g

7.

1 point

The lowest practical altitude for a satellite orbiting the Earth is about

600 miles

200 km

10km

24000 miles

8.

1 point

the force of gravity between two people standing next to each other is

zero

greater than 1 lb

small but measurable

too small to measure

9.

1 point

Skyhook, if built, is

a way to get to high orbits

a way to get into space using less energy

faster way to get into space

safer way to get to sapce

10.

1 point

artificial gravity can be created in a spaceship by

accelerating the ship

there is no such thing

moving at high veloctiy

using ion engines

11.

1 point

Someone firing a rifle is pushed back by the rifle. This illustrates that

angular energy is conserved

momentum is conserved

angular moment is conserved

energy is conserved

12.

1 point

If you fall for 1s, your speed will be approximately

78 km/h

100 km/h

35 km/h

5 km/h

13.

1 point

If an artificial satellite orbited the Earth at 384 000 km (the distance to the Moon), it would orbit the Earth in a period of

1 day

1 week

1 month

90 mins

14.

1 point

Orbital velocity is about

8 miles per sec

7 miles per sec

5 miles per sec

11 miles per sec

15.

1 point

Rockets fly by

being lighter than air

pushing air downwards

using anitgravity

pushing fuel downward

16.

1 point

A problem with rail guns is that

they use too much energy to be practical

they violate momentum conservation

the high acceleration can cause damage

they are limited to about the speed of sound

17.

1 point

If satellites fly too low, they will crash because

lower air density

of air resistance

of weaker gravity

of stronger gravity

18.

1 point

Airplanes fly (maintain their altitude) by

pushing air up

pushing air downward

pushing air forward

pushing air backward

19.

1 point

The storm surge in a hurricane comes from

the force of winds on the buildings.

the low pressure

increased gravity

the strong waves

20.

1 point

a typical spy satellite can continuously observe a location on the ground for about

10 sec

1 min

90 min

12 hrs

21.

1 point

A rail gun

can shoot bullets faster than ordinary gun

doesnt really accelerate things

accelerates rails

uses ions for propulsion

22.

1 point

The orbit of GPS is

GEO (same as HEO)

TEO

LEO

MEO

23.

1 point

Spy satellites usually fly at

MEO

HEO

escape velocity

LEO

24.

1 point

At an altitude of 200 km, the downward force of gravity on an Earth satellite is

zero

the same as on the surface of the earth

about half as strong as on the surface

a little bit weaker

25.

1 point

A cubic meter helium balloon can lift

50 pounds

about 1 kg

1 gram

100 pounds

26.

1 point

a geosynchronous satellite orbits the earth

once every 90 mins

once every 6 hrs

once every 24 hrs

once every month

27.

1 point

When an astronaut sneezes in space, his head is snapped back with a higher velocity than on Earth, because

there is no air in space

Wrong! His head is not snapped back with a higher velocity.

his head is massless

momentum is conserved

28.

1 point

Balloons rise until

the surrounding air becomes too cold

the surrounding air becomes too thin (not dense)

they reach space.

the surrounding air becomes too dense

29.

1 point

The Sun is mostly hydrogen, yet the Earth has very little hydrogen gas. That's because

it combined with carbon to make hydrocarbons

it escaped to space

it combined with oxygen to make water

it was burned by fusion when the early earth was hot

30.

1 point

the method that would take the least energy to get something to space is

launching it in a 3 stage rocket

lifting it by elevator

flying it into a ballon

using an ion rocket

31.

1 point

The sun would be a black hole if it were squeezed into a radius of

2000 miles

2 million miles

2 miles

its already is a black hole

32.

1 point

For very high velocities, the best kind of rocket to use is

ion rocket

hydrogen/oxygen

TNT

hot air rocket

33.

1 point

Ice-skaters spin faster by pulling in their arms. This illustrates that

angular momentum is conserved

angular energy is conserved.

energy is conserved

momentum is conserved