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3 years ago

a car advertisement States that a certain car can accelerate from rest to70km/h in 7seconds find the car's average acceleration

Physics

1 answer:

Aneli [31]3 years ago

8 0

Answer:

Acceleration is 2.78 m/s²

Explanation:

Since the car is from rest, initial velocity, u is zero.

from first newton's equation of motion:

${ \bf{v = u + at}} \\$

v is final velocity

u is initial velocity

a is acceleration

t is time

70 km/h is (70 × 1000 ÷ 3600) m/s = 19.44 m/s

${ \sf{19.44 = 0 + (a \times 7)}} \\ { \sf{7a = 19.44 }} \\ { \sf{a = 2.78 \: {ms}^{ - 2} }}$

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Explanation:

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$E = \dfrac{F}{q }$

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3 years ago

A uniform steel girder of weight 22KN and of length 12m is lifted off the ground at one end by means of a crane. When the raised

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Answer:

Explanation:

For free body diagram see attached sheet .

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Answer:

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Explanation:

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v₀ = 0 m/s

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Δy = v₀ t + ½ at²

Δy = (0 m/s) (10.0 s) + ½ (39.2 m/s²) (10.0 s)²

Δy = 1960 m

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Find: Δy

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Δy = 7840 m

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a car advertisement States that a certain car can accelerate from rest to70km/h in 7seconds find the car's average acceleration​

a car advertisement States that a certain car can accelerate from rest to70km/h in 7seconds find the car's average acceleration