A 0.60-kg particle has a speed of 2.0 m/s at point A and a kinetic energy of 7.5 J at point B. What is (a) its kinetic energy at A? (b) Its speed at point B ? (c) The total work done on the particle as it moves from A to B ?

(a) 1.2 J

(b) 5 m/s

(c)  6.3 J

Explanation:

(a) Kinetic energy at A

Ek = 1/2mv² Equation 1

Where Ek = Kinetic energy at A, m = mass of the particle, v = velocity at A.

Given: m = 0.6 kg, v = 2.0 m/s

Substitute into equation 1

Ek = 1/2(0.6)(2²)

Ek = 0.6(2)

Ek = 1.2 J.

(b)

Speed at point B

Ek' = 1/2mv'² Equation 2

Make v' the subject of the equation,

v' = √(2Ek'/m) Equation 3

Where, Ek' = kinetic energy at B, v' = velocity at B.

Given: Ek' = 7.5 J, m = 0.6 kg,

Substitute into equation 3

v' = √[(2×7.5)/0.6]

v' =√(15/0.6)

v' = √25

v' = 5 m/s.

(c)

Wt =  Δ kinetic energy from A to B

Where Wt = total work done as the particle moves from A to B.

Wt = 1/2m(v'²-v²)

Wt = 1/2(0.6)(5²-2²)

Wt = 0.3(25-4)

Wt = 0.3(21)

Wt = 6.3 J

are their multiple choices ?

explanation:

the order for strong to weak forces such as

strong nuclear force → electromegnetic force → weak nuclear force → gravitational force

the fundamental forces are those forces that act between to objects or element to make interactions. there are four types of fundamental forces such as strong and weak nuclear forces (due to protons and electrons), electromagnetic force (due to the motion of electrons) and gravitational force (due to orbital movement of the planet). if these forces are arranged on the basis of their maximum strength then the order is

strong nuclear force → electromegnetic force → weak nuclear force → gravitational force