in case one, a car speeds up from zero m/s to 15 m/s. in case two, the same car speeds up from 15 m/s to 30 m/s. the mass of the

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in case one, a car speeds up from zero m/s to 15 m/s. in case two, the same car speeds up from 15 m/s to 30 m/s. the mass of the

car is 1000 kg. compare the energy needed to provide the increase in speed in each case. give your answers in joules. (a) in case one, how much energy is needed? j (b) in case two, how much energy is needed? j (c) in case two, how many more times the energy was needed than in case one? three times as much energy was needed. four times as much energy was needed. the same amount of energy was needed in both cases. twice as much energy was needed.

Physics

1 answer:

GrogVix [38] · Answer 1 · 2024-07-19T14:46:28+03:00

Three time the energy was needed than in case one.

What is energy?

In physics, energy is the quantifiable property that is transmitted to a body or a physical system and is visible in the form of heat and light. The law of conservation of energy states that energy can be converted in form but cannot be created or destroyed.

Case 1:

Vo = 0 m/s

V1 = 15 m/s

Case 2:

Vo = 15 m/s

V1 = 30 m/s

Change in KE = 1/2 × m × (V1^2 - Vo^2)

KE1 = 1/2 × 1000 × (15^2 - 0)

= 112.5 kJ

KE2 = 1/2 × 1000 × (30^2 - 15^2)

= 1/2 × 1000 × 675

= 337.5kJ