Answer:
0.75
Explanation:
Since the static frictional force is the maximum force applied just before sliding, our frictional force, F is 300 N.
Since F = μN where μ = coefficient of static friction and N = normal force = 400 N (which is the downward force applied against the surface).
So, μ = F/N
= 300 N/400 N
= 3/4
= 0.75
So, the coefficient of static friction μ = 0.75
Answer:
(C) The frequency decrease and intensity decrease
Explanation:
The Doppler effect describes the change in frequency or wavelength of a wave in relation to an observer who is moving relative to the wave source, or the wave source is moving relative to the observer, or both.
if the observer and the source move away from each other as is the case for this problem, the wavelength heard by the observer is bigger.
The frequency is the inverse from the wavelength, so the frequency heard will increase.
The sound intensity depends inversely on the area in which the sound propagates. When the buzzer is close, the area is from a small sphere, but as the buzzer moves further away, the wave area will be from a larger sphere and therefore the intensity will decrease.
Answer:
2. 200N
3.50kg
4.700N
Explanation:
Weight is another word for the force of gravity
Weight is a force that acts at all times on all objects near Earth.
F=m*g
where g=acceleration due to gravity
2. due to the gravitational fields of the earth , assume gravitational acceleration=10m/s2
F=20*10= 200N
3.same as above
mass=Force/gravitational acceleration
mass=500/10 = 50kg
4.force=mass*gravitational acceleration
force=70*10=700N
