Answer:
v = 29.4 m / s
Explanation:
For this exercise we can use the conservation of mechanical energy
Lowest starting point.
Em₀ = K = ½ m v²
final point. Higher
= U = m g h
Let's use trigonometry to lock her up
cos 60 = y / L
y = L cos 60
Height is the initial length minus the length at the maximum angle
h = L - L cos 60
h = L (1- cos 60)
energy is conserved
Em₀ = Em_{f}
½ m v² = mgL (1 - cos 60)
v = 2g L (1- cos 60)
let's calculate
v² = 2 9.8 3.0 (1- cos 60)
v = 29.4 m / s
Answer:
N = 19.6 N
Explanation:
Given that,
Mass of a block, m = 2000 g
1 kg = 1000 g
It means, 2000 g = 2kg
We need to find the value of normal force on the block on a table. Normal force is balanced by the weight of the block as follows :
N = mg, g is acceleration due to gravity
N = 2 kg × 9.8 m/s²
N = 19.6 N
So, the normal force acting on the block is 19.6 N.
The best answer is D.
Stress is a force that acts on rock to change its shape or volume. Because stress is a force, it adds energy to the rock, which is stored in the rock until either the rock breaks or changes shape.
There are three kinds of stress, namely shearing, tension and compression.
Shearing- force that pushes a mass of rock in two opposite directions and can cause rock to break and slip apart or change shape.
Tension - force that pulls on the crust, stretching rock so that it becomes thinner in the middle.
Compression - force that squeezes rock until it folds or breaks