PHY 1014 ALL HOMEWORK

A hunter fires a bullet from a horizontally-held rifle while simultaneously dropping another bullet from the side of the rifle. Which bullet hits the ground first?

both hit at the same time

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

Water pressure is greatest against the

bottom of a submerged object

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

decrease.

An empty jar is pushed open side downward into water so that air trapped inside can't escape. As it is pushed deeper, the buoyant force on the jar

decreases

As water in a confined pipe speeds up, the pressure it exerts against the inner walls of the pipe

decreases

For each degree a volume of air at 0°C is cooled, its pressure

decreases by 1/273

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

decreases.

If a loaf of bread is compressed, its

density increases

The pressure in a liquid depends on liquid

depth and density

The air in this room has

energy, weight, mass

Compared to the buoyant force on you when floating in fresh water, buoyant force on you when floating in the dense water of the Dead Sea is

equal to your weight

If a battleship sinks in a canal lock, the water level in the lock

fall

Blood pressure is normally greater in your

feet

Very importantly, a hydraulic press can multiply

forces

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

forget it; you can't travel far enough

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

four times as much.

When you touch a hot penny in sunlight with your finger, energy flows

from the penny to your finger.

The Sun is spherical due to

gravitation

Lobsters live on the bottom of the ocean. Compared with the density of seawater, the density of a lobster is

greater

Airplane lift is achieved when air pressure on the bottom of a wing is

greater than pressure on top.

When gas in a container expands to twice its volume, its density

halves

Compared to a giant iceberg, a hot cup of coffee has

higher temperature, but less thermal energy

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

increases.

Compared with an empty ship, the same ship loaded with Styrofoam will float

lower in the water

Whether one object is warmer than another object has most to do with

molecular kinetic energy.

The force of gravity acts on all apples on an apple tree. Some apples are twice as far from the ground. Such twice-as-high apples of the same mass, have

practically the same weight.

When you stand on tiptoes on a bathroom scale, there is an increase in

pressure on the scale, not registered as weight

Buoyant force acts upward on a submerged object because

pressure up on bottom is greater than downward pressure on top of the object.

When a suction cup sticks to a wall it is

pushed to the wall by the atmosphere

If your mass and the mass of Earth remained the same while the Earth's radius was halved, your weight would

quadruple

If your mass remains unchanged while both the mass of Earth and its radius doubles, your weight

reduces by half.

Roll a bowling ball off the edge of a table. As it falls, its horizontal component of motion

remains constant.

When an ice cube in a glass of water melts, the water level

remains the same

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 and remains in a vertical path. The projectile will

rise and fall back to Earth's surface.

Weight can be simulated in a space vehicle if the vehicle is

rotating.

Buoyant force is greatest on a submerged 1 cubic centimeter block of aluminum or lead

same on each

Two life preservers have identical volumes, one filled with Styrofoam and the other filled with sand. When both life preservers are fully submerged, the buoyant force is greater on the one filled with

same on each if volumes remain the same

Strictly speaking, gas pressure inside an inflated stretched balloon is

slightly greater than air pressure outside the balloon

Compared with the buoyant force of the atmosphere on a 1-L helium-filled balloon, the buoyant force of the atmosphere on a nearby 1-L solid iron block is

the same

Pumice is a volcanic rock that floats. Compared with the density of water, its density is

the same

If a pressure of 20 kPa is applied to one piston in a simple hydraulic device, the pressure on a piston of larger area will be

the same 20 kPa.

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

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

the same as its initial speed.

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.

The speeds of the planets about the Sun depend on

their distances from the Sun.

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

their tangential velocities.

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

1 s

What is the buoyant force acting on a 10-ton ship floating in the ocean?

10 tons

How deep must an inverted drinking glass be pushed beneath the surface of water so that the volume of enclosed air is squeezed to half?

10.3 m

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 weigh there?

100 N

Escape speed from Earth is

11.2 km/s.

The density of air at room temperature is about 0.0012 grams/cm3. Estimate the mass of air inside an average automobile.

2 kg

It would be easier to pull evacuated Magdeburg hemispheres apart if they were

2 km above the ocean surface

A volume of helium gas has a temperature of 10°C. The same gas twice as hot has a temperature of

293°C.

The temperature of melting ice is

32F and 0 C

What is the force of gravity on a 500-N woman standing on Earth's surface?

500 N

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°

The amount of gravitational force that acts on a space vehicle that orbits Earth is

nearly as much as the vehicle's weight on Earth's surface

At absolute zero, a substance has

no more energy to give up

For the astronauts inside an orbiting space vehicle, there is no force of Earth's gravity acting on them. This statement is

always false.

A swimmer cannot snorkel more than a meter deep because air

at the surface will not freely enter the higher-pressure region in the compressed lungs

The International Space Station orbits at an average 360-km altitude so that it is mainly above Earth's

atmosphere

In the vacuum of outer space, there is no

atmospheric pressure.

If the volume of an object were to double with no change in mass, its density would

be half

A bubble of air released from the bottom of a lake

becomes larger as it rises.

The fastest moving planet in a solar system is

the planet nearest the Sun.

The lowest temperature concievable in nature is

-273°C

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

0.5 s.

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

Earth.

Thermal energy can be measured in

Joules, calories, Calories

The planet Neptune was discovered by perturbations of

Uranus.

If the Sun were twice as massive,

its pull on the Earth would double and Earth's pull on the Sun would double.

) If a room is cold it is due to a

lack of adequate thermal energy.

A lobster crawls onto a bathroom scale submerged on the ocean bottom. Compared to its weight above the surface, its apparent weight under water is

less

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.

Minimal orbit speed about Earth is about 8 km/s. Minimal orbital speed 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.

What prevents satellites such as the space shuttle from falling?

nothing, they continually fall around and around Earth

Which is the smallest unit of measurement for temperature?

one Fahrenheit degree

A 1-ton blimp hovers in air. The buoyant force acting on it is

one ton

Heat is thermal energy that flows due to

temperature differences.

Newton discovered

that gravity is universal.

Escape speed for a rocket is less from

the Moon.

The reason a life jacket helps you float is that

the combined density of you and the jacket is less than your density alone

There is a legend of a Dutch boy who bravely held back the Atlantic Ocean by plugging a leak near the top of a dike with his finger until help arrived. Which of the following is most likely?

the force on his finger would have been less than 1 N

The pair of water-filled caissons of the Falkirk Wheel have equal weights when

they carry unequal weights of floating boats. they carry equal-weight floating boats. one carries a heavy floating boat and the other only water.

Suspend a pair of Ping-Pong balls from two strings so there is a small space between them. If you blow air between the balls, they will swing

towards each other

The motion of molecules that most affects temperature is

translational motion

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 mass of one planet is doubled, and the distance between them doesn't change, then the force between them is

twice as much

When a chocolate bar is cut in half, its density is

unchanged

A change in pressure at any point in a confined fluid at rest is transmitted

undiminished to all points in the fluid.

A fish normally displaces its own

volume and weight of water

A completely submerged object always displaces its own

volume of fluid.

A rising balloon is buoyed up with a force equal to the

weight of air it displaces.

Atmospheric pressure is caused by the

weight of the atmosphere.

Inside a freely falling elevator you would experience no

weight.

Passengers in a high-flying jumbo jet feel their normal weight in flight. Passengers in an orbiting space vehicle do not because passengers are

without support forces.