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17. A 100 kg CAR TRAVELS AT 11 m/s. WHAT AMOUNT OF WORK WOULD BE REQUIRED TO

BRING IT TO A SPEED OF 5 m/s?
A. 1045 J
B. -1045 J
C. 4800 J
D. -4800 J

18. A 70 kg ICE SKATER GLIDES AT A SPEED OF 6 m/s ACROSS THE ICE. DETERMINE THE
SKATER'S KINETIC ENERGY.
A. 420 J
B. 1260 J
C. 210 J
D. 105 J

User Meshaal
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1 Answer

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Step-by-step explanation:

17) the amount of work needed in Joules will be equal to the change in Kinetic Energy (1/2 m v^2) of the car

1/2 (100 kg) ( 5 ^2 - 11^2 ) = -4800 J

18) K E = 1/2 m v^2 = 1/2 * 70 * 6^2 = 1260 J

User Abstraktor
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