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4 years ago

A car accelerates at 3 m/s*2. Assuming the car starts from rest, how much time does it need to

Physics

2 answers:

Eduardwww [97]4 years ago

6 0

We are given with some parameters used in Kinematics for determining the motion of an object.

Accleration = 3 m/s²
Started from rest (Initial vel.) = 0 m/s
Final velocity = 12 m/s

We have to find the time taken by the car to attain the final velocity with the given accleration. By using 1st equation of motion which says:

v = u + at

Final velocity = Initial velocity + Accl. × Time taken

Plugging the values,

➝ 12 = 0 + 3(t)

➝ 3t = 12

➝ t = 4 s

So, the correct answer is Option C. And we are done...

Carry On Learning $!$

uranmaximum [27]4 years ago

5 0

<h3><u>Given</u><u>:</u><u>-</u></h3>

Acceleration,a = 3 m/s²

Initial velocity,u = 0 m/s

Final velocity,v = 12 m/s

<h3><u>To</u><u> </u><u>be</u><u> </u><u>calculated:-</u><u> </u></h3>

Calculate the time take by a car.

<h3><u>Solution:-</u><u> </u></h3>

According to the first equation of motion:

v = u + at

★ Substituting the values in the above formula,we get:

⇒ 12 = 0 + 3 × t

⇒ 12 = 3t

⇒ 3t = 12

⇒ t = 12/3

⇒ t = 4 sec

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oksian1 [2.3K]

Answer:

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Explanation:

Given;

angular displacement of the blade, θ = 90.08⁰

duration of motion of the blade, t = 0.4 s

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The centripetal acceleration is calculated as;

a = ω²r

a = (3.93)² x 0.45

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3 years ago

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bija089 [108]

Answer:

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2 years ago

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marishachu [46]

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4 years ago

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densk [106]

Answer;

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3 years ago

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Mila [183]

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As per the question:

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