A)Ep'=mgh=mgl(1-cosa).At the bottom of the swing Ep=0(reference level),so the potential energy as the child is just released is bigger than the potential energy at the bottom of the swing.;B)The speed of the child at the bottom of the swing-->v=√(2gh)=√[2gl(1-cosa)];C)I don't think that the tension does any work.
Maybe this will help you out:
Momentum is calculate by the formula:
Where:
P = momentum
m = mass
v = velocity
The SI unit:
So the unit of momentum would be:
Impulse is defined as the change in momentum or how much force changes momentum. It can be calculate with the formula:
I = FΔt
where:
I = impulse
F = Force
Δt = change in time
The SI unit:
F = Newtons (N) or 
t = Seconds (s)
So the unit of impulse would be derived this way:
I = FΔt
I = x 
or
You can then cancel out one s each from the numerator and denominator and you'll be left with:
So then:
Momentum: Impulse
Answer:
Explanation:
given.
magnification(m) = 400 x
focal length (f_0)= 0.6 cm
distance between eyepiece and lens (L)= 16 cm
Near point (N) = 25 cm
focal length of the eyepiece (f_e)= ?
using equation
Answer:
0.02
Explanation:
coefficient of kinetic friction = μ
force of friction = Ff
Normal Force = FN, but
FN = -W
Ff = -μFN
so μ = Ff/FN
= 4N/200N
= 0.02.
Answer:
The effect of your walking will create a force on the airline acting downwards, due to the weight. By Newton's thirds law the airline will exert an equal and opposite reaction force directed downwards.
Explanation:
The weight of all the passengers acts downwards on the floor of the Airplane.
The Airplane exerts an equal and opposite force on the passengers, with the help of its propulsion due to which the flight keeps on flying without falling down.
Hence by changing the frame of reference we can observe the force which is responsible for the reaction.
