<u>Acceleration</u> is the rate at which <u>velocity</u> changes.
Answer:
1.06 secs
Explanation:
Initial speed of sled, u = 8.4 m/s
Final speed of sled, v = 5.8 m/s
Coefficient of kinetic friction, μ = 0.25
Using the impulse momentum theory, we know that the impulse applied to the sled is equal to change in momentum of the sled:
FΔt = mv - mu
where m = mass of the object
Δt = time interval
F = force applied
The force applied on the sled is the frictional force, which is given as:
F = -μmg
where g = acceleration due to gravity
Therefore:
-μmgΔt = mv - mu
-μmgΔt = m(v - u)
-μgΔt = v - u
Making Δt subject of formula:
Δt = (v - u) / -μg
Δt = (5.8 - 8.4) / (-0.25 * 9.8)
Δt = -2.6/ -2.45
Δt = 1.06 secs
It took the sled 1.06 secs to travel from A to B.
Answer:
1. What type of wave is sound?
2.Does sound need a medium to travel through?
3. What are the properties of sound waves?
Explanation:
1. The type of waves sound are is mechanical waves.
2. Sound needs a solid, liquid or gas (material medium) to travel through.
3. I believe they are wavelength, amplitude, frequency, time period and velocity.
I apologize if it is incorrect-
I hope it helps! Have a great day!
Anygays-
By the work energy theorem, the total work done on the stone is given by its change in kinetic energy,

We have


Then the total work is
