Physics 2 Test

Which system is in a state of stable equilibrium? A marble in the bottom of a spherical bowl. A Marble on top of a spherical bowl. A marble on a flat, level surface. A marble rolling down an inclined surface.

A marble in the bottom of a spherical bowl.

You are riding a very fast Ferris Wheel so that you actually notice a variation in your apparent weight. Where is your apparent weight maximum? At the top At the bottom Halfway up, going down Halfway up, going up

At the bottom

Consider an elastic ball that is falling downward toward the ground. The ball hits the ground and then begins traveling upward again. At what point in the trip does the ball have the most energy stored in it as elastic potential energy? At the bottom of the path when it is not moving, right before it rebounds. After it has rebounded and left the ground. Right before it hits the ground When it is moving the fastest.

At the bottom of the path when it is not moving, right before it rebounds.

At various times in the news it has been reported that certain vehicles are susceptible to rolling over. The physical mechanism that is responsible for rollovers is Frictional torques about the driver only. Frictional torques from the vehicle on the road acting below the road's center of mass. Frictional torques from the road on the vehicle about its center of mass, which is higher in taller vehicles. Strong air currents simply blowing the vehicle over.

Frictional torques from the road on the vehicle about its center of mass, which is higher in taller vehicles.

A top is Statically stable and dynamically unstable. Statically unstable and dynamically stable. Statically unstable and dynamically unstable. Statically stable and dynamically stable.

Statically unstable and dynamically stable.

Cars are designed so that their bodies buckle (permanently deform) when they are in an accident. How does the buckling make the car safer by not allowing it to recoil (bounce) so much? The buckling stores energy. The buckling dissipates the energy of the crash. The buckling provides energy to the crashing objects. The buckling gives the car a high coefficient of restitution.

The buckling dissipates the energy of the crash.

For your high school science project you are able to get community support and terraform Mars, so that liquid water could exist on its surface. Suppose you have two cans of soda - one barely floats and one barely sinks in fresh water on Earth. Taking them to Mars, with the gravitational acceleration being 1/3 its value on earth, Both objects will now float because they are lighter. The buoyant behavior of the two objects will be the same. Both objects will sink because the water is lighter. The one that sank will now float and the one that floated will now sink.

The buoyant behavior of the two objects will be the same.

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

The weight of fluid displaced is less than its weight.

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

The weight of the fluid displaced equals the object's weight.

Suppose you are spending your weekend on roller skates trying to get momentum from somewhere. Which of the following will give you momentum in the south direction? Throwing your keys southward. Throwing your keys northward. Bending down and throwing your keys straight up. (B) or (C).

Throwing your keys northward.

Suppose you had a very long straw that could reach from a cup of water on the ground level to the top of a very tall building. When you suck on the straw in order to bring water up, You could drink the water at any height with no problem You could bring the water up to only a certain height in the straw because the atmosphere pushes down on the surface of the water by a given amount. You could bring the water up to only a certain height in the straw because after it will flash freeze in the cup. Water is too thick to be pulled up in the straw by more than a few inches.

You could bring the water up to only a certain height in the straw because the atmosphere pushes down on the surface of the water by a given amount.

A bathroom scale reads Your weight Your apparent weight The force with which the earth attracts you Your mass in kg

Your apparent weight

You are riding a multi-speed bicycle up a steep hill that's 100 m high and want to do as little work as possible on your way up the hill. You should choose the largest crank sprocket (attached to the pedals) and the smallest freewheel sprocket (attached to the rear wheel). You should choose the smallest crank sprocket (attached to the pedals) and the largest freewheel sprocket (attached to the rear wheel). You should choose the largest crank sprocket (attached to the pedals) and the largest freewheel sprocket (attached to the rear wheel). Your choice of gears doesn't matter because you'll do the same amount of work climbing the hill no matter which gear you choose.

Your choice of gears doesn't matter because you'll do the same amount of work climbing the hill no matter which gear you choose.

Suppose you are standing on a bathroom scale when you are flying in a jet airplane. For a moment the scale reads more than your actual weight. During that moment, it's exerting an upward force on you that is greater than your weight and you are accelerating upward. accelerating downward. not accelerating. accelerating sideways.

accelerating upward.

Pressure is area divided by force. force divided by area. a type of force. force times area.

force divided by area.

The maximum speed a rocket can achieve is the speed of light the speed of sound. equal to the speed of its exhaust plume. less than the speed of its exhaust plume. greater than the speed of its exhaust plume but less than the speed of light.

greater than the speed of its exhaust plume but less than the speed of light.

You are taking a shower in your dormitory when someone flushes a toilet nearby. The pressure in the cold water line drops and you find yourself showering in what feels like molten lava. This loss of cold water pressure occurs when the toilet lets cold water flow through the pipes delivering it to the bathroom and the water's speed in those pipes increases. Assuming all the piping to be about on the same level, the cold water's faster motion in the delivery pipes reduces its pressure in the shower head because faster moving water has less pressure than slower moving water. has less kinetic energy than slower moving water. has less gravitational potential energy than slower moving water. losses more energy to viscous drag as it flows through the delivery pipes.

has less pressure than slower moving water.

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

honey's large viscosity favors laminar flow.

You stop for a cappuccino at a coffee shop and notice that the tiny white bubbles of steamed milk remain on the surface of the coffee. These air-filled bubbles stay where they are, rather than descending into the coffee or rising into the air, because they are less dense than the coffee but more dense than the air above the coffee. more dense than the coffee but less dense than the air above the coffee. lighter than the cup of coffee but heavier than the column of air above the coffee. thicker than the coffee but less thick than the air above the coffee.

less dense than the coffee but more dense than the air above the coffee.

The pressure gradient set up in water standing is a glass is an example of ________ ________ in pressure, while variations in pressure due to water flowing faster in the smaller parts of a pipe are a type of ________ ________ in pressure. static variation; buoyant force static variation; dynamic variation dynamic variation; constant value dynamic variation; dynamic constancy

static variation; dynamic variation

You are extremely bored during the long summer months when school is out of session, so you decide to attach a graphing calculator to a rubber band and repeatedly bounce it up and down vertically. When the rubber band is at its maximum stretch away from your hand the calculator's velocity is downward but its acceleration is upward. the calculator's velocity is zero but its acceleration is upward. the calculator's velocity is upward but its acceleration is downward. the calculator's velocity is zero but its acceleration is downward.

the calculator's velocity is zero but its acceleration is upward.

When you throw a tennis ball against the floor at an angle, the direction of the vertical component of its velocity reverses. the horizontal component of its velocity reverses. the speed of the ball reverses. the vertical component of its velocity doubles.

the direction of the vertical component of its velocity reverses.

The pressure in a water pipe is always lower in regions where the water moves faster only when the pipe increases in altitude towards the faster fluid end the pipe is level. anything other than water is in the pipe the pipe is made of plastic

the pipe is level.

The pressure in a water pipe may not necessarily be lower in regions where the water moves faster when the pipe is not level the pipe is level. the pipe is in zero gravity. the pipe is in free fall.

the pipe is not level

You work with a catering firm and have been given a challenge. By emptying several liquid beverage dispensers, you have to rank them in order of their content (which one is fullest, next fullest, etc.) Having had a physics class, you devise a scheme to compare the speeds of the fluids exiting the spouts at the bottom of the containers. The principle you base your prediction on is: the volume is lower so the speed is lower. what were you thinking!? The speeds won't depend upon fluid level the speed increases when there is more air in the jug. the pressure (and hence water level) is lower when the speed is lower.

the pressure (and hence water level) is lower when the speed is lower.

It is important for cyclists to lean their bicycles while negotiating sharp turns because the torque created by their leaning balances out the frictional torque from the road which would tend to flip them. the torque created by their leaning balances out their weight and holds them up. their tires flatten out, thus getting better traction on the road. they increase their static stability

the torque created by their leaning balances out the frictional torque from the road which would tend to flip them.

Some engineers have suggested that we can simulate gravity in outer space by having a circular rotating space station where persons feel an outward - directed fictitious force due to the rotation of the station. The reason they feel such a force is because their velocity is toward the center of the space station and their inertia tends to keep them moving outward. the fictitious force is always in the direction of centripetal acceleration. they are accelerating toward the center of the space station and inertia tends to keep them moving sideways. their velocity is away from the center of the space station and their inertia tends to make them move in towards the center.

they are accelerating toward the center of the space station and inertia tends to keep them moving sideways.

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

they are in a constant state of free - fall.