PHY 160 Final exam review

What is the mass of a person (in kilograms)?

What is the weight (gravitational force) of a person (in newtons)?

Here is a 5 kg box sitting on a table. What forces are acting on the box? How large is each force, and what direction is it? Are any of these forces directly related to forces acting on the table?

Here is a 5 kg box sitting on a table in an elevator. The elevator is moving down with constant speed 2 m/sec. What forces are acting on the box? How large is each force, and what direction is it? Are any of these forces directly related to forces acting on the table?

Here is a 5 kg box sitting on a table in an elevator. The elevator is moving down with speed 2 m/sec but accelerating upward at 1 m/s 2 What forces are acting on the box? How large is each force, and what direction is it? Are any of these forces directly related to forces acting on the table?

Here is a 5 kg box sitting on a table. Prof. Troland gave it a shove and then left for France. Right now the box is moving at 2 m/s, and there is a 2 N force due to friction. What forces are acting on the box?

Here is a 5 kg box sitting on a table. Prof. Troland gave it a shove and then left for France. Right now the box is moving at 2 m/s, and there is a 2 N force due to friction. What forces are acting on the box? 50 N down due to gravity 50 N up due to the table 2 N to the left due to friction What is the net force on the box?

Here is a 5 kg box sitting on a table. Prof. Troland gave it a shove and then left for France. Right now the box is moving at 2 m/s, and there is a 2 N force due to friction. What is the net force on the box? 2 N to the left, because the upward and downward forces balance out. What is the acceleration of the box?

Here is a 5 kg box sitting on a table. Prof. Troland gave it a shove and then left for France. Right now the box is moving at 2 m/s, and there is a 2 N force due to friction. What is the acceleration of the box? Net force = 2 N = mass * acceleration = 5 kg * acceleration = 5 kg * 0.4 m/s 2 How long (time) will the box continue sliding before it stops?

Here is a 5 kg box sitting on a table. Prof. Troland gave it a shove and then left for France. Right now the box is moving at 2 m/s, and there is a 2 N force due to friction. The acceleration of the box is 0.4 m/s 2 to the left How long (time) will the box continue sliding before it stops? acceleration = (change in velocity)/time -0.4 m/s 2 = (0 – 2 m/s)/time Time = 5 seconds.

Here is a 5 kg box sitting on a table. Prof. Troland gave it a shove and then left for France. Right now the box is moving at 2 m/s, and there is a 2 N force due to friction. What is the kinetic energy of the box? How much energy does the box lose if it slides 2 m?

Here is a 5 kg box sitting on a table. Prof. Troland gave it a shove and then left for France. Right now the box is moving at 2 m/s, and there is a 2 N force due to friction. What is the kinetic energy of the box? K.E. = ½ (5 kg) (2 m/s) 2 = 10 Joules How much energy does the box lose if it slides 2 m? Energy transferred = - 2N x 2 m = -4 Joules The kinetic energy of the box is now 6 Joules.

Here is a 5 kg box sitting on a table. Prof. Troland gave it a shove and then left for France. Right now the box is moving at 2 m/s, and there is a 2 N force due to friction. The kinetic energy of the box is 10 J. How far will it slide before coming to a stop?

Here is a 5 kg box sitting on a table. Prof. Troland gave it a shove and then left for France. Right now the box is moving at 2 m/s, and there is a 2 N force due to friction. The kinetic energy of the box is 10 J. How far will it slide before coming to a stop? Final KE = Initial KE + energy transferred = 10 J – 2N * distance = 10 J - 2N * 5 m

Here is a 5 kg box sitting on a table. Prof. Troland gave it a shove and then left for France. Right now the box is moving at 2 m/s, and there is a 2 N force due to friction. The box will slide 5 m before coming to a stop, and this will take 5 seconds. What is the average speed of the box during this process?

Here is a 5 kg box sitting on a table. Prof. Troland gave it a shove and then left for France. Right now the box is moving at 2 m/s, and there is a 2 N force due to friction. The box will slide 5 m before coming to a stop, and this will take 5 seconds. What is the average speed of the box during this process? Average speed = distance/time = 5 m/5 s = 1 m/s ?? What does this have to do with the 2 m/s we started with?

Here is a 5 kg box sitting on a table. Prof. Troland gave it a shove and then left for France. Right now the box is moving at 2 m/s, and there is a 2 N force due to friction. The box will slide 5 m before coming to a stop, and this will take 5 seconds. What is the average speed of the box during this process? Average speed = distance/time = 5 m/5 s = 1 m/s ?? What does this have to do with the 2 m/s we started with?

The battery pack for an electric car consists of a dozen 12 V batteries connected as shown in the diagram (each box is a 12 V battery). The largest current that can be drawn from a single battery is 20 Amperes. What is the voltage of this battery back?

The battery pack for an electric car consists of a dozen 12 V batteries connected as shown in the diagram (each box is a 12 V battery). The largest current that can be drawn from a single battery is 20 Amperes. How much current can the battery provide?

The battery pack for an electric car consists of a dozen 12 V batteries connected as shown in the diagram (each box is a 12 V battery). The largest current that can be drawn from a single battery is 20 Amperes. How much electrical power can the battery provide?

This diagram shows a laser beam and two prisms. Draw lines that show what happens to the laser beam after it has gone through both prisms.

A window is covered by a shade with very small holes in it. When the sun shines on the shade, there are round disks of light on the opposite wall. What causes this? Disks??

Mr. Stick wants a mirror to put on the wall, that will let him see all of himself at once. How large does the mirror have to be, and where should it be? Where is Mr. Stick’s image?

Mr. Stick wants a mirror to put on the wall, that will let him see all of himself at once. How large does the mirror have to be, and where should it be?

Why is a car that is driving fast on an icy day in danger of going off the road? Why does the car go off the road at all?

Why is a car that is driving fast on an icy day in danger of going off the road? If the car stays on the road, what net force is acting on it?

A 500 kg car drives up the hill shown at a constant speed 10 m/s. What is the increase in potential energy? Did the kinetic energy change? How much power did the engine deliver?

A 500 kg car drives up the hill shown at a constant speed 10 m/s. Potential energy increase = weight * height = 500 N * 20 m = 1000 J Did the kinetic energy change?

A 500 kg car drives up the hill shown at a constant speed 10 m/s. Kinetic energy = ½ mass * (velocity) 2 did not change. How much power did the engine deliver?

A 500 kg car drives up the hill shown at a constant speed 10 m/s. The car got up the hill in 4.5 seconds. Power = (energy increase)/(time interval) = 1000 J/4.5 sec = 222 Watt

Where is the moon today? What does it look like? When does it rise?

Full moon was December 6; today is 5 days later. It rose at 10 PM yesterday, set at 11 AM today.