Answer:
(A) -2940 J
(B) 392 J
(C) 212.33 N
Explanation:
mass of bear (m) = 25 kg
height of the pole (h) = 12 m
speed (v) = 5.6 m/s
acceleration due to gravity (g) = 9.8 m/s
(A) change in gravitational potential energy (ΔU) = mg(height at the bottom- height at the top)
height at the bottom = 0
= 25 x 9.8 x (0-12) = -2940 J
(B) kinetic energy of the Bear (KE) =
= = 392 J
(C) average frictional force =
- change in KE (ΔKE) = initial KE - final KE
- ΔKE = -
- when the Bear reaches the bottom of the pole, the final velocity (Vf) is 0, therefore the change in kinetic energy becomes ΔKE = - 0 = 392 J
\frac{-(ΔKE+ΔU)}{h}[/tex] =
= = 212.33 N
The answer is; The cloud is cool and lies between you and a hot star.
Absorption lines occur when the electrons of an atom absorb energy through a specific wavelength of light and the electrons ‘jumps’ from a lower energy level to a higher energy level. Absorption lines are viewed as black lines in a continuous spectrum
A net torque of magnitude is 600
Infrared waves are ineffective for treating cancer because they do not transfer enough energy to destroy cancer cells.
<h3>Importance of high frequency waves</h3>
One of the uses of a high frequency wave is in the treatment of cancer. These high frequency waves transfer enough energy to destroy the cancer cells.
E = hf
where;
- f is frequency of the wave
Infrareds have low frequency, and hence low energy.
Thus, infrared waves are ineffective for treating cancer because they do not transfer enough energy to destroy cancer cells.
Learn more about high frequency here: brainly.com/question/1807992
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