Q1:

A 150-W lightbulb emits of its energy as electromagnetic radiation. The bulb is at the center of a perfectly light absorbing sphere of radius 10.00 m. What is the radiation pressure on the sphere’s interior?

• A N/m2
• B N/m2
• C N/m2
• D N/m2
• E N/m2

Q2:

A microscopic spherical dust particle of radius 2.000 μm and mass 10.0 µg is moves in outer space at a constant speed of 30.0 cm/s. A wave of light strikes the particle from the opposite direction to the direction of the particle’s motion and this light is absorbed. The particle decelerates uniformly to rest in a time of 1.00 s. What was the average electric field amplitude of the absorbed light?

• A V/m
• B V/m
• C V/m
• D V/m
• E V/m

Q3:

Electromagnetic radiation from a 5.00-mW laser is concentrated into a 1.00-mm2-area beam.

What is the radiation intensity of the beam?

• A W/m2
• B W/m2
• C W/m2
• D W/m2
• E W/m2

What is the maximum electric force that the beam can exert on a 2.00-nC electric charge?

• A N
• B N
• C N
• D N
• E N

What is the maximum magnetic force that the beam can exert on a 2.00-nC charge that has a speed of 400 m/s?

• A N
• B N
• C N
• D N
• E N

Q4:

Sunlight falls perpendicularly on a kite with a reflecting surface of area 0.75 m2. The average intensity of the sunlight is 900 W/m2.

What is the average force on the kite due to radiation pressure?

• A N
• B N
• C N
• D N
• E N

If the kite material is black and absorbs all sunlight, what is the average force on the kite due to radiation pressure?

• A N
• B N
• C N
• D N
• E N