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3 years ago

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The initial speed of a body is 7.1 m/s. What is its speed after 2.23 s if it accelerates uniformly at 2.64 m/s 2 ? Answer in uni

ts of m/s. What is its speed after 2.23 s if it accelerates uniformly at −2.64 m/s 2 ? Answer in units of m/s

1 answer:

Nana76 [90]3 years ago

5 0

13.0m/s

1.2m/s

Explanation:

Given parameters:

Initial speed of the body = 7.1m/s

time taken = 2.23s

Acceleration = 2.64m/s²

Unknown:

Final speed = ?

Solution:

Acceleration is the rate of change of velocity with time.

a = $\frac{V - U}{T}$

a = acceleration

V = final speed

U = initial speed

T = time taken

Input the variables and solve for V;

2.64 = $\frac{V - 7.1}{2.23}$

V - 7.1 = 5.9 expression 1

V = 5.9 + 7.1 = 13.0m/s

B

Using the same parameters, the speed after a uniform deceleration of -2.64m/s², the negative sign implies deceleration;

from expression 1;

V - 7.1 = -5.9

V = -5.9 + 7.1 = 1.2m/s

learn more:

Acceleration brainly.com/question/3820012

#learnwithBrainly

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