Work needed = 23,520 J
<h3>
Further explanation
</h3>
Given
height = 12 m
mass = 200 kg
Required
work needed by the crane
Solution
Work is the transfer of energy caused by the force acting on a moving object
Work is the product of force with the displacement of objects.
Can be formulated
W = F x d
W = Work, J, Nm
F = Force, N
d = distance, m
F = m x g
Input the value :
W = mgd
W = 200 kg x 9.8 m/s²x12 m
W = 23520 J
T = 3.5 secs
Velocity (v) = g * t = 10 m/s^2 * 3.5 sec = 35 m/s
<h3>Answer;</h3>
<em>Energy is transferred.</em>
<h3>Explanation;</h3>
- Work is the force applied over a given distance, in other words work is the product of force and distance. That is; Work = force × distance.
- Work is measured in Joules.
- Energy on the other hand, is the ability to do work.
- According to the principle of work-energy a change in the kinetic energy is equivalent to the net work don e by the object. Therefore, when work is being done energy is being transferred from one point to another.
OPTION C The car is accelerating because the direction of velocity is changing explains why a race car going around a curve is accelerating, even if the speed is constant
- When a body is in uniform circular motion ( constant speed ), it will continuously cheanges its direction and so the body is accelerating
- The rate at which an item changes its velocity is known as acceleration, a vector variable. If an object's velocity is changing, it is accelerating.
- As a vector quantity, acceleration has a direction attached to it. The acceleration vector's direction is determined by two factors: if the thing is slowing down or speeding up the direction the thing is travelling in (+ or -)
- The following general rule is used to calculate acceleration:
An object's acceleration will be in the opposite direction of its velocity if it is slowing down.
You may use this basic concept to determine if an object's acceleration is positive or negative, to the right or left, up or down, etc.
To know more about acceleration visit : brainly.com/question/12550364
#SPJ4