Answer:
W = 47040 J
Explanation:
Given that,
The mass of a student, m = 60 kg
Height of the tower, h = 80 m
We need to find the work done in climbing the tower. The work done is given by :
W = mgh
So,
W = 60 × 9.8 × 80
W = 47040 J
So, the required work done is 47040 J.
Explanation:
Terminal velocity is given by:
Here, m is the mass of the falling object, g is the gravitational acceleration, 
is the drag coefficient, 
is the fluid density through which the object is falling, and A is the projected area of the object. in this case the projected area is given by:
Recall that drag coefficient for a horizontal skydiver is equal to 1 and air density is 
.
Without drag contribution the motion of the person is an uniformly accelerated motion, thus:
Answer:
Explanation:
The direction of the acceleration is in the same direction as the net force causing it. F = ma is actually a vector equation in which f and a are both vectors and m is a scalar constant.
Answer:
83.67 m/s
Explanation:
Set up a calculation to convert units of measure to what you need.
You have km/s and you need m/s.
4.08km 1000 m 83.67m
----------- X ---------- = --------------- the km will cancel out and you are left
12.0 s 1 km s with m/s
Answer:
0.8895m
Explanation:
Cable diameter = 0.0125m
Mass of elevator = 6450kg
Young Modulus(E) = 2.11*10¹¹N/m
∇l (change in length) =
L = 362m
A = Πr², but r = d / 2 = 0.0125 / 2 = 0.00625m
A = 3.142 * (0.00625)² = 1.227*10^-4m²
Young Modulus (E) = Tensile stress / Tensile strain
E = (F / A) / ∇l / L
F = mg = 6450 * 9.8 = 63210N
2.11*10¹¹ = (63210 / 1.22*10^-4) / (∇l / 362)
2.11*10¹¹ = 5.18*10⁸ / (∇l / 362)
2.11*10¹¹ = (5.18*10⁸ * 362) / ∇l
2.11*10¹¹ = 1.875*10¹¹ / ∇l
∇l = 1.875*10¹¹ / 2.11*10¹¹
∇l = 0.8895m
The change in length is 0.8895m
