Answer:
W = 34.64 ft-lbs
Explanation:
given,
Horizontal force = 4 lb
distance of push, d = 10 ft
angle of ramp, θ = 30°
Work done on the box = ?
We know,
W = F.d cos θ
W = 4 x 10 x cos 30°
W = 40 x 0.8660
W = 34.64 ft-lbs
Hence, work done on the box is equal to W = 34.64 ft-lbs
Answer:
Form of energy: Example
1. Light energy: Electromagnetic radiation
2. Nuclear energy: Nuclear fission
3. Chemical energy: Energy stored in plant matter
4. Electrical energy: Lightning
5. Thermal energy: A hot surface
6. Sound energy: A tuning fork
7. Solar energy: Energy from the Sun
8. Mechanical energy: A moving vehicle
Answer:
Time, t = 0.87 seconds
Explanation:
Given that,
Initial velocity of the object, u = 4.3 m/s
The coefficient of kinetic friction between horizontal tabletop and the object is 0.5
We need to find the time taken by the object for the object to come to rest i.e. final velocity will be 0.
Using first equation of motion to find it as :

a is the acceleration, here, 


So, the time taken by the object to come at rest is 0.87 seconds. Hence, this is the required solution.
Velocity. Since velocity consists of a speed and a direction, acceleration is a change in speed, or direction, or both.