Answer:
0.3 m
Explanation:
Initially, the package has both gravitational potential energy and kinetic energy. The spring has elastic energy. After the package is brought to rest, all the energy is stored in the spring.
Initial energy = final energy
mgh + ½ mv² + ½ kx₁² = ½ kx₂²
Given:
m = 50 kg
g = 9.8 m/s²
h = 8 sin 20º m
v = 2 m/s
k = 30000 N/m
x₁ = 0.05 m
(50)(9.8)(8 sin 20) + ½ (50)(2)² + ½ (30000)(0.05)² = ½ (30000)x₂²
x₂ ≈ 0.314 m
So the spring is compressed 0.314 m from it's natural length. However, we're asked to find the additional deformation from the original 50mm.
x₂ − x₁
0.314 m − 0.05 m
0.264 m
Rounding to 1 sig-fig, the spring is compressed an additional 0.3 meters.
ANSWER:
3408.81 kg
STEP-BY-STEP EXPLANATION:
Given:
v = 111 m/s
Ek = 21000000 J
We have that the formula for kinetic energy is as follows:

We substitute the values given in the exercise and solve for m (mass)

The mass of the helicopter is 3408.81 kilograms.
You want to draw a free body diagram of the forces on the sled in the horizontal x-direction.
If you visualize the system in an x-y coordinate plane, the force along the x-direction is the angle it makes with the x-axis multiples by the force.
The angle made with the x-axis is cosine of the angle theta.
Please see picture attached.
C. The object is not in motion, ruling out A. We are not adding mass in any way, nor does adding heat to object increase its mass, therefore also ruling out B. Finally, we are not changing the object's position in such a way that gives it a higher ability to do work, ruling out D.
Light travels at the speed of 186,000 miles per second. If you were to travel around the earth it would be 7.5 times in a second