Answer:
the is D
Explanation:
An action-reaction force pair
I think it’s physical change, because the objects aren’t changing into another substance, just changing their physical shape. Hope this helps!
2) Higher frequency and higher pitch.
Due to the Doppler effect, sounds emitted at a distance have a higher frequency and therefore a higher pitch.
Answer:
x' = 1.01 m
Explanation:
given,
mass suspended on the spring, m = 0.40 Kg
stretches to distance, x = 10 cm = 0. 1 m
now,
we know
m g = k x
where k is spring constant
0.4 x 9.8 = k x 0.1
k = 39.2 N/m
now, when second mass is attached to the spring work is equal to 20 J
work done by the spring is equal to


x'² = 1.0204
x' = 1.01 m
hence, the spring is stretched to 1.01 m from the second mass.
Answer:
Δt=0.85 seconds
Explanation:
In this chase the speed does not change as the mass change.So we can use the follow equation to find the required time
Δt=Δv/gμ
To stop the final speed will be zero therefore the change in speed will be
Δv= vf-vi
Δv=0-5 m/s
Δv= -5 m/s
Now we plug our values for Δv,g and μ to find time
Δt=Δv/gμ
Δt=(-5m/s) ÷(9.8m/s² × 0.6)
Δt=0.85 seconds