Momentum
1. An air bag applies a force of 2000 N to bring about a change in momentum of 240 kg m/s. How much time did it act over?
0.12 s
1. Which of the following cannot be measured directly with a digital multimeter?
power
1. A physicist has three mystery materials, A, B, and C. She shines light from one material into another and records which direction the light bends, obtaining the following result:
B, C, A
1. If a wave has a frequency of 220 Hz and a wavelength of 8.00 m, then what is the speed of this wave?
1760 m/s
1. A motor spins because the magnetic field of an electromagnet in the motor changes direction, alternately attracting and repelling a permanent magnet. What causes the magnetic field to change direction?
2. A 1300 kg car with the brakes applied comes to a stop in 5.30 s. During these 5.30 s the force of friction slowing down the car is 2300 N. What is the change in momentum of the car?
12200 kg m/s
2. If you have a circuit with one battery and one resistor and want to measure the current flowing through the resistor, how would you do it?
Connect an ammeter in series with the resistor.
2. A light ray shines from Material 1 (n = 2.30) into Material 2 (n = 1.90). For what incident angle below does total internal reflection occur?
) 66.8°
2. An electromagnetic wave traveling at 3.0 × 108 m/s has a 0.61 m wavelength. What is the frequency of this wave?
4.9×108 Hz
2. Which of the following is an example of a magnetic force within an electric motor?
3. Jimi (80 kg) and Tony (100 kg) stand motionless on ice skates, facing each other at arm's length on a smooth, frozen pond. Which of the following actions will give Tony the greatest speed?
Tony pushes Jimi with 200 N of force for 0.08 s.
3. A circuit consists of a battery plus two resistors connected in parallel with each other. How do you connect the probes from a digital multimeter in order to measure the current through one of the resistors in this circuit?
Connect the probes in series with the resistor.
3. Light traveling through an unknown material strikes amber (n = 1.55) at an angle of incidence of 55° and undergoes total internal reflection. Which of the following could be the unknown material?
cubic zirconia (n = 2.15)
3. Which of the following is an example of a longitudinal wave?
the rumbling sound from a tractor
3. Which of the following statements best expresses the right-hand rule for an electric current and the magnetic field it produces?
4. A moving object with a mass of 7.7 kg has linear momentum of magnitude 26 kg m/s. What is the kinetic energy of the object?
44 J
4. What voltage is required to cause 5.0 A to flow in the circuit below if the resistance is 15 Ω?
75 V
4. A material has an index of refraction of 1.62. What is the critical angle of this material when it is surrounded by air, which has an index of refraction of 1.00?
38.1°
4. Which of the following terms are needed to describe a water wave but not the motion of a car on a freeway?
wavelength, velocity, amplitude
4. A motor spins because the magnetic field of an electromagnet in the motor changes direction, alternately attracting and repelling a permanent magnet. What causes the magnetic field to change direction?
5. A bowling ball has a mass of 3.6 kg and is traveling with a velocity of 13 m/s down the lane. How much momentum does it have?
47 kg m/s
5. What current will flow if the battery produces 10 V in the circuit below and the resistance is 750 Ω?
0.013 A
5. A ray of light in air (n = 1.00) enters water (n = 1.33) at an angle of 50°. What is the angle of refraction?
5. A sound wave has a frequency of 380 Hz. What is the period of this wave?
0.0026 s
5. A transformer is used to convert 1080 V to 120 V for home use. What is the ratio of the number of turns in the primary coil to the number of turns in the secondary coil?