The answer for this question would be choice "<span>B. The average annual dose of background radiation is 250 times smaller than the dose linked to increased cancer risk."
You only have to compare 4.0 x 10^-4 and 1.0 x 10^-1. And if you can observe carefully, when you try to multiply the average annual dose of background radiation by 250, you would get 0.1 which is equivalent to the amount of annual dose linked to increased cancer risk. Therefore, the answer is B.</span>
Answer:
Among force and impulse, There is a lesser calculation for impulse. Also, it has same dimensions as momentum. Hence that is most closely related.
Answer:
300
Explanation:
work done=force×displacement
=60*5=300J
power=work done/time
=300/3=100Js
Answer:
<h2>3</h2>
Explanation:
Using the efficiency formula. Efficiency = MA/VR * 100%
MA = Mechanical Advantage
VR = velocity ratio =
Distance moved by effort = 4.5m
distance moved by load = 1.5m
VR = 4.5/1.5 =3
Assuming efficiency is 100% (since friction can be ignored)
100% = MA/3 * 100%
1 = MA/3
MA = 3*1
MA = 3
Mechanical Advantage of the ramp is 3
The energy carried by the incident light is
where h is the Planck constant and f is the frequency of the light. The threshold frequency is the frequency that corresponds to the minimum energy needed to eject the electrons from the metal, so if we substitute the threshold frequency in the formula, we get the minimum energy the light must have to eject the electrons: