If both waves have the same wavelength, then the amplitude of
their sum could be anything between 1 cm and 9 cm, depending
on the phase angle between them.
If the waves have different wavelengths, then the resultant is a beat
with an amplitude of 9 cm.
Answer: -49m/s.
Explanation:
As the rock only falls, we will assume that the initial vertical velocity is zero.
We neglect the air friction, so the only force acting on the rock is the gravitational force, this means that the acceleration is -g = -9.8m/s^2.
Then we can write:
a(t) = -9.8m/s^2
To write the velocity of the rock, we must ingrate over time and get:
v(t) = (-9.8m/s^2)*t + v0
where v0 is the initial vertical velocity, and as we said above, v0 = 0m/s
Then the vertical velocity as a function of time is:
v(t) = (-9.8m/s^2)*t
Now, the question is:
"...If a rock falls for 5 seconds near the surface of the earth and with no air friction, it will reach a velocity of..."
Then we need to evaluate the velocity equation in t = 5 seconds.
v(5s) = (-9.8m/s^2)*5s = -49m/s.
Answer:
False
Explanation:
Protons are positively charged, electrons are negatively charged, and neutrons have no charge.
Answer:
The rate of work is 360 W
Explanation:
Given:
Speed of block 
Upward acceleration of block 
Mass of block 
kg
First Find the force act on block due to gravity
Where 
N
For finding at what rate motor doing work when it is pulling the block upward,
W
Therefore, the rate of work is 360 W
