I'm not sure if this is correct but it's what I'll do
This is free-fall problem.
Stone A is thrown upward, at the point it falls down to the place where it was thrown, the velocity is -15m/s.
Now I choose the bridge is the origin. From the bridge, stone A and B fall the same distance which means Ya = Yb ( vertical distance )
Ya = Vo(t + 2) + 1/2a(t+2)^2
= -15(t + 2) + 1/2(9.8)(t^2 + 4t + 4)
= -15t - 30 + 4.5(t^2 + 4t + 4)
= -15t - 30 + 4.5t^2 + 18t + 18
= 4.5t^2 +3t - 12
Yb = Vo(t) + 1/2a(t)^2
= 0 + 4.5t^2
4.5t^2 = 4.5t^2 +3t - 12
0 = 3t - 12
4 = t
Time for Stone B is 4s
Time for Stone A is 6s
The horizontal force needed to start the calculator moving from rest is 1.5 N
What is Kinetic friction?
It is defined as a force that acts between moving surfaces.
The magnitude of the force will depend on the coefficient of kinetic friction between the two materials.
Here,
weight of calculator, N = 3 N
The coefficients of static frictions, µ (static) = 0.50
The coefficients of kinetic frictions, µ (kinetic) = 0.40
Now,
The horizontal force required = The static friction force
F = µ (static) * weight of calculator
F = 0.50 * 3.0
F = 1.5 N
Hence,
The horizontal force needed to start the calculator moving from rest is 1.5 N
Learn more about horizontal force here:
<u>brainly.com/question/21481680</u>
<u />
#SPJ4
Answer:
there are go fella hope u understood
The answer for this would be A. since power is Joules/seconds and energy is rated in Joules
Answer is C: Ability to see three-dimensional images of the surfaces of object
Explanation:
To enable the technician see fractures and broken particles in a better resolution as the SEM sees the peaks and valley of the structure.