Define 1 joule of work (b) Certain force acting on a 25 kg mass changes its velocity from 6 m/s to 4 m/s. Calculate the work done by the body.
Answers
Answer:
Work is said to be done when a force applied to an object moves that object. Work done is generally referred to in relation to the force applied while energy is used in reference to other factors such as heat.
Kinetic energy is given by the expression,
(K. E)v = 1/2 mv2
Where,
K. E = Kinetic energy of the object
v = velocity of the object
Kinetic energy when the object was moving with a velocity of 5 m/s
(K. E)5 = 1/2 × 20 × (5)2
(K. E)5 = 250 J
Kinetic energy when the object was moving with a velocity 2 m/s
(K. E)2 = 1 /2 × 20 × (2)2
(K. E)2 = 40 J
Work done = Change in kinetic energy
= 40 J – 250 J
= – 210 J
Answer:
The work done is - 250J.
Explanation:
Work done:
Work in physics is the energy that is transferred to or from an item when a force is applied along a displacement. For a constant force acting in the same direction as the motion, the work is simply equal to the product of the force's magnitude and the distance traveled.
The change of kinetic energy is work done.
Given that the mass of the object is 25 kg and its velocity changes from 6 m/s to 4 m/s.
Initial kinetic energy = K₁ = 1/2 mv₁²
1/2 mv₁² = 1/2 × 25 × 6² = 450 J
Final kinetic energy = K₂ = 1/2 mv₂²
1/2 mv₂² = 1/2 × 25 × 4² = 200 J
The changes of kinetic energy is
Final kinetic energy - Initial kinetic energy
=K₂ - K₁
= 200J - 450J
= -250 J
To learn more about kinetic energy, click on the below link:
https://brainly.in/question/26671
https://brainly.in/question/30179901
#SPJ3