physics 101 test 2 Wiley plus

What mass has a rest energy of 100J? A: 1.1x10-15 kg B: 3x10-8 kg C: 3.3x10-7 kg D: 0.01 kg

A: 1.1x10^15kg

What is the gravitational force that two 100 kg persons exert on each other when standing 1m apart? A: 6.672x10^-7 N B: 1 N C: 6.672x10^-11 N D: 10,000 N

A: 6.672x10^-7 N

Aerodynamic forces consist of A: drag and lift. B: drag, lift and buoyancy. C: drag and gravity. D: lift and drop.

A: drag and lift

A curve ball in baseball curves because of A: lift forces. B: drag forces. C: gravitational forces. D: buoyant forces.

A: lift forces

Fluids have viscosity because A: the atoms and molecules within the fluid interact with each other, producing internal frictional forces. B: the atoms and molecules within the fluid are heavy and hard to push.. C: molecules in fluids are long and get tangled. D: they are always in contact with some boundary.

A: the atoms and molecules within the fluid interact with each other, producing internal frictional forces.

In studying many martial arts, it is necessary to practice efficient and safe postures. One important concept related to how one should stand is that the feet should be reasonably far apart, because A: the base of support is wider, thus stabilizing the person. B: the weight on each foot will be less than when standing normally. C: the weight on each foot will be more than when standing normally. D: the friction force increases, giving the person more traction.

A: the base of support is wider, thus stabilizing the person

For an object that sinks in a fluid, A: the weight of fluid displaced is less than its weight. B: the weight of the fluid displaced is greater than the object's weight. C: the weight of the fluid displaced equals the object's weight. D: the weight of the object becomes more than in air.

A: the weight of fluid displaced is less than its weight

In a popular classroom demonstration, a cotton ball is placed in the bottom of a strong test tube. A plunger fits inside the tube and it makes an airtight seal. It is then pushed down very rapidly, and the cotton flashes and burns. This happens because A: when the air was compressed its temperature increased. B: friction between the plunger and the tube ignited the cotton. C: cotton contains a pressure-sensitive substance that burns upon impact. D: it's one of those demos that nobody understands.

A: when the air was compressed its temperature increased.

Atmospheric pressure is about 100000 Pa. At what depth in water does this pressure double? A: 1 m B: 10 m C: 100 m D: 1000 m

B: 10m

The relativistic momentum of a 1000 kg car moving at 0.95 times the speed of light is: A: 9.13x10^8 kg m/s B: 9.13x10^11 kg m/s C: 3200 kg m/s D: 2.85x10^11 kg m/s

B: 9.13x10^11 kg m/s

Why will a rolled - up ball of aluminum foil float in water but solid aluminum will sink? A: It won't - the ball will sink. B: Due to the air inside, the average density of the ball is lower than water. C: Aluminum is less dense than water anyway. D: Water cannot get in to equalize the pressure.

B: Due to the air inside, the average density of the ball is lower than water.

As the Reynolds number decreases, A: flow is becoming more laminar. B: flow is going from being viscous dominated to inertia dominated and therefore turbulent. C: flow is slowing down. D: flow is speeding up.

B: flow is going from being viscous dominated to inertia dominated and therefore turbulent.

At what place in or near the jet engine is gas moving the fastest relative to the flying airplane? A: In the air flowing into the engine's inlet duct. B: In the plume of exhaust gas flowing out of the engine's outlet duct. C: In the engine's turbine D: In the engine's compressor

B: in the plume of exhaust gas flowing out of the engine's outlet

Astronauts in the space shuttle feel weightless because A: they are so far away from the center of the Earth. B: they are in a constant state of free-fall. C: they are moving very rapidly. D: there is no atmosphere where they are.

B: they are in a constant state of free-fall

Why are failures in dams more likely to occur closer to the bottom of the dam? A: Water is considerably more dense at the bottom. B: Water pressure is higher at the bottom. C: The temperature is higher at the bottom. D: Water weighs more at the bottom.

B: water pressure is higher at the bottom.

How far apart would two 100 kg persons need to be so that the force they exert on each other is equal to 1N? You can assume they are point masses, having mass but no size. A: 1m B: 6.672x10^-7 m C: 8.17x10^-4 m D: 100 m

C. 8.17x10-4m

The relativistic energy of a 1000 kg car moving at 0.95 times the speed of light is: A: 1000 J B: 2.8x10^17 J C:2.9x10^20 J D: 9.3x10^11 J

C: 2.9x10^20 J

Water weighs about 10 N per liter on Earth. A 4.0 liter ball is pushed underwater on the space shuttle, where gravity was 1/10 that on Earth. What is the buoyant force on the ball? A: 1N B: 10 N C: 4 N D: 40 N

C: 4N

When a fluid is in steady - state flow and its path bends, the pressure on the outside of the bend is always A: Equal to the pressure everywhere else in the fluid. B: Lower than the pressure on the inside of the bend. C: Higher than the pressure on the inside of the bend. D: Darned near infinite.

C: higher than the pressure on the inside of the bend

Compared to planets close to the sun, and based upon Kepler's third law of planetary motion, the length of the year of planets farther out from the sun are A: the same. B: less. C: larger. D: More information is necessary.

C: larger

Rockets receive their forward propulsion through A: pushing against the ground and objects in space. B: mass conservation of the rocket and fuel. C: pushing against the exhaust. D: small aerodynamic forces.

C: pushing against the exhaust

You are riding in a hot air balloon. You have not used the burner for some time and the balloon begins to sink. Assuming that no air is allowed to leave or enter the balloon, A: the average density of the balloon remained constant and the buoyant force on the balloon became less than its weight. B: the average density of the balloon became greater than the surrounding air and the buoyant force on the balloon remained constant. C: the average density of the balloon became greater than the surrounding air and the buoyant force on the balloon became less than its weight. D: the balloon became heavier.

C: the average density of the balloon became greater than the surrounding air and the buoyant force on the balloon became less than its weight.

For an object that is floating on a fluid, A: the weight of fluid displaced is less than its weight. B: the weight of the fluid displaced is greater than the object's weight. C: the weight of the fluid displaced equals the object's weight. D: the weight of the object becomes less than in air.

C: the weight of the fluid displaced equals the object's weight

For an object that is neutrally buoyant in a fluid, A: the weight of fluid displaced is less than its weight. B: the weight of the fluid displaced is greater than the object's weight. C: the weight of the fluid displaced equals the object's weight. D: the object has zero weight.

C: the weight of the fluid displaced equals the object's weight

A fan can be used to circulate air around a room. The pressure at the inlet side of the fan is A: less than the pressure at the outlet side and less than atmospheric pressure. B: less than the pressure at the outlet side but more than atmospheric pressure. C: equal to the pressure at the outlet side. D: more than the pressure at the outlet side.

D. more than the pressure at the outlet side

The diameter of a pipe is tripled while the pressure difference across the pipe remains the same. The volume flow rate of the pipe increases by a factor of A: 3 B: 9 C: 27 D: 81

D: 81

A curve ball's path bends to the right as it flies toward home plate because it is experiencing an aerodynamic force to its right. One reason why the ball is experiencing this aerodynamic force is that the ball is spinning and that spin A: causes the air to flow more rapidly around the left side of the ball than around the right side of the ball. B: exerts a torque on the ball that causes its angular momentum to shift toward the left. C: exerts a torque on the ball that causes its angular momentum to shift toward the right. D: causes the air to flow more rapidly around the right side of the ball than around the left side of the ball.

D: causes the air to flow more rapidly around the right side of the ball than around the left side of the ball.

Suppose you have two containers with liquid in them. One has a density of 760 kg/m3 and the other has a density of 910 kg /m3. If an object floats in one container and sinks in the other, the density of the object A: has a value equal to the difference in densities of the two liquids. B: must have a value equal to the average densities of the two liquids. C: has a value less than 760 kg/m3 or greater than 910 kg/m3. D: has a value between 760 kg/m3 and 910 kg/m3.

D: has a value between 760 kg/m3 and 910

Flowing honey is less likely to become turbulent than flowing water because A: honey's large density favors laminar flow. B: water's large viscosity favors turbulent flow. C: water's large pressure favors turbulent flow. D: honey's large viscosity favors laminar flow.

D: honey's large viscosity favors laminar flow.

When a fish hovers over the bottom of a lake, what forces act on it, and what is the net force? A: Lift only, for a net force up. B: Lift only, for a net force zero. C: Lift and weight, for a net force up. D: Lift and weight, for a net force zero.

D: lift and weight, for a net force zero

If a golf ball were smooth rather than dimpled, it would A: travel much too far after being hit by a golf club. B: curve toward the left after being hit by the club of a right-handed golfer. C: curve toward the right after being hit by the club of a right-handed golfer. D: not travel as far after being hit by a golf club.

D: not travel as far after being hit by a gold club

Gravity creates A: constant motion in fluids. B: lack of pressure on the top of all fluids C: uniform pressure in fluids. D: pressure gradients in fluids.

D: pressure gradients in fluids.

When driving down a level smooth road, your car tires flatten at the bottom and they nicely support the weight of your car. However when you run over a small pointed rock the tire is punctured and fails. The rock is able to puncture the tire because A: the car has much more kinetic energy when on the rock than when on the flat road and this kinetic energy becomes potential energy in the tire. B: when the car is on the rock almost all its weight is on the tire over the rock. C: the car has much more gravitational potential energy when on the rock than when on the flat road and this gravitational potential energy becomes pressure potential energy in the tire. D: the small surface area of the rock times the pressure in the tire is not enough force to support the car. Thus, the tire fails.

D: the small surface area of the rock times the pressure in the tire is not enough force to support the car. Thus, the tire fails.

The four things that affect the amount of water flowing through a hose are A: air viscosity, hose length, inlet and outlet pressures and hose diameter. B: water viscosity, hose composition, inlet and outlet pressures and hose diameter. C: water viscosity, hose length, inlet pressure and hose diameter. D: water viscosity, hose length, inlet and outlet pressures and hose diameter.

D: water viscosity, hose length, inlet and outlet pressures and hose diameter.

The maximum speed a rocket can achieve is A: the speed of light. B: the speed of sound. C: equal to the speed of its exhaust plume. D: less than the speed of its exhaust plume. E: greater than the speed of its exhaust plume but less than the speed of light.

E: greater than the speed of its exhaust plums but less than the speed of light

Which of the following would cause a household fan to stall? A. The blades are too sharply angled for the speed the fan rotates. B: B. The fan is rotating too fast. C: C. (A) and (B) D: D. The fan is rotating too slowly and can't push the air around.

c: (A) and (B)