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2 years ago

A truck accelerates to a velocity of 38 m/s over 755 m of road

Physics

1 answer:

den301095 [7]2 years ago

6 0

1) The acceleration is $0.96 m/s^2$

2) The time taken is 39.6 s

Explanation:

Since the motion of the truck is a uniformly accelerated motion (=constant acceleration), we can use the following suvat equation:

$v^2-u^2=2as$

where

v is the final velocity

u is the initial velocity

a is the acceleration

s is the distance covered

For the truck in this problem,

u = 0 (it starts from rest)

v = 38 m/s

s = 755 m

Solving for a, we find the acceleration:

$a=\frac{v^2-u^2}{2s}=\frac{38^2-0}{2(755)}=0.96 m/s^2$

For this part we can use the following suvat equation

$v=u+at$

where

v is the final velocity

u is the initial velocity

a is the acceleration

t is the time taken for the velocity to change from u to v

In this problem,

u = 0

v = 38 m/s

$a=0.96 m/s^2$

Solving for t,

$t=\frac{v-u}{a}=\frac{38-0}{0.96}=39.6 s$

Learn more about accelerated motion:

brainly.com/question/9527152

brainly.com/question/11181826

brainly.com/question/2506873

brainly.com/question/2562700

#LearnwithBrainly

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Answer:

To not exceed the 5,000 characters, see each answer with its explanation below.

Explanation:

Question 1.

A feather and a rock dropped at the same time from the same height would land at the same time when dropped by an astronaut on the moon.

The shape and mass of the feather that falls vertically down, through the air, cause the resistance of the air, that opposes the gravitational attraction of the Earth, to be considerably large, compared to the case of the rock.

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When the soccer ball is kicked, the action and reaction forces do not cancel each other out because the forces act on two different objects.

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increases as the force on the object increases.

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All answers listed. ← correct answer

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