No, he did not perform any work. Work is when you’re using energy which results in a force. Even though he was tired and sweaty, he did not move the boulder. So therefore he did not perform any work.
False, rubber is a poor conductor but is a good insulator.
Answer:
the work done by friction on the car is 524,582 J.
Explanation:
Given;
mass of the roller coaster, m = 800 kg
distance moved by the coaster, d = 225 ft = 68.58 m
final velocity of the coaster, v = 80 mi/h = 35.76 m/s
The time taken for the coaster to drop down the hill is calculated as;
The work done by friction on the car is calculated as;
Therefore, the work done by friction on the car is 524,582 J.
Our atmosphere would be quickly stripped away, much like what apparently happened on Mars after its molten core cooled and solidified. The spinning Earth core is what helps create our magnetic field, without which means no Van Allen Belts, which mean solar radiation becomes more lethal than just sun burn
Answer: a) 152 cm
b) 0.725 ms
c) 10°
Explanation:
Given
Frequency of the wave, f = 524 Hz
Speed of the wave, v = 345 m/s
Wavelength of the wave, λ = ?
The relation for wavelength is given by
λ = f/v, on substituting
λ = 524 / 345
λ = 1.52 m or 152 cm
T = 1/v
T = 0.0029 s
T = 2.9 ms.
Note that the phase change is 90°, thus the time required to change the phase by 90° is
t = 2.9 * (90 / 360)
t = 2.9 * 0.25
t = 0.725 ms
The phase difference at a particular instance 4.4 cm apart is
= (4.4 / 152) * 360
= 0.02895 * 360
= 10.422°
a) 152 cm
b) 0.725 ms
c) 10°
