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3 years ago

A 0.54 kg particle has a speed of 5.0 m/s at point A and kinetic energy of 7.5 J at point B. What is

Physics

1 answer:

Wewaii [24]3 years ago

4 0

<u>Answers</u>

(a) 6.75 Joules.

(b) 5.27 m/s

<u>Explanation</u>

Kinetic energy is the energy possessed by a body in motion.

(a) its kinetic energy at A?

K.E = 1/2 mv²

= 1/2 × 0.54 × 5²

= 6.75 Joules.

(b) its speed at point B?

K.E = 1/2 mv²

7.5 = 1/2 × 0.54 × V²

V² = 7.5 ÷ 0.27

= 27.77778

V = √27.77778

= 5.27 m/s

Work done = 7.5 - 6.75

= 0.75 Joules

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Answer: A) Force = 3.841*10^-18 N.

B) force (f) is 4.30* 10^12 times greater than the weight (Fg).

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u = initial velocity = 2.40 * 10^5 m/s

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Force = 3.841*10^-18 N.

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Answer:

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B = 0.50exp(-20t) T

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