Answer:
2 seconds
Explanation:
v = at + v₀
19.62 m/s = (9.81 m/s²) t + 0 m/s
t = 2 s
Answer:
The wavelength of wave is 7.5 meter.
Given:
Speed of wave = 1500 
Frequency of wave = 200 Hz
To find:
Wavelength of wave = ?
Formula used:
Where 
= wavelength of the wave
v = speed of wave
n = frequency of wave
Solution:
Wavelength of wave is given by,
Where = wavelength of the wave
v = speed of wave
n = frequency of wave
= 7.5 m
The wavelength of wave is 7.5 meter.
Answer:
C. Burning coal tends to harm the environment more than using solar panels.
Explanation:
When coal is burned, it reacts with the oxygen in the air. This reaction converts the stored potential energy, which turns into thermal energy, which is released as heat. But it also produces methane and carbon dioxide which is released into the air.
From the equations of linear motion,
v² = u² + 2as where v is the final velocity, u is the initial velocity and a is the gravitational acceleration, and s is the displacement,
Thus, v² = u² -2gs, but v=0
hence, u² = 2gs
= 2×9.81×0.43
= 8.4366
u = √8.4366
=2.905 m/s
Hence the initial velocity is 2.905 m/s
Then using the equation v= u +gt .
Therefore, v = u -gt. (-g because the player is jumping against the gravity)
but, v = 0
Thus, u= gt
Hence, t = u/g
= 2.905/9.81
= 0.296 seconds
