Answer:(a)891.64 N
(b)0.7
Explanation:
Mass of crate 
Crate slows down in 
initial speed 
inclination 
From Work-Energy Principle
Work done by all the Forces is equal to change in Kinetic Energy




change in kinetic energy

(b)Coefficient of sliding friction



and 


Answer:
Explanation:
Given that,
Spring constant = 16N/m
Extension of spring
x = 8cm = 0.08m
Mass
m = 5g =5/1000 = 0.005 kg
The ball will leave with a speed that makes its kinetic energy equal to the potential energy of the compressed spring.
So, Using conservation of energy
Energy in spring is converted to kinectic energy
So, Ux = K.E
Ux = ½ kx²
Then,
Ux = ½ × 16 × 0.08m²
Ux = 0.64 J
Since, K.E = Ux
K.E = 0.64 J
Answer:
18 times
Explanation:
According to the security purposes which is set under the rules and regulation OSHA, which describes all the rights to the worker.
In the boom hoist receiving system all the sheaves which are used should have a pitch diameter of rope not less than 18 times the diameter of the nominal rope which is used.
Answer: 9938.8 km
Explanation:
1 pound-force = 4.48 N
30.0 pounds-force = 134.4 N
The force of gravitation between Earth and object on the surface of is given by:

Where M is the mass of the Earth, m is the mass of the object, R (6371 km) is the radius of the Earth.
At height, h above the surface of the Earth, the weight of the object:

we need to find "h"
taking the ratio of two:

Hence, Pete would weigh 30 pounds at 9938.8 km above the surface of the Earth.