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Olenka [21]
3 years ago
12

The velocity of a car teduces from 30 km/h as the car approaches a stop sigh. Is this an example of positive or negative acceler

ationthe
Physics
1 answer:
tresset_1 [31]3 years ago
5 0

<u>Answer:</u>

The stopping car has negative acceleration.

<u>Explanation:</u>

 We know acceleration is the rate of change of velocity. That is

            Acceleration(a) = ( Final velocity - Initial velocity )/ Time taken.

            Here Final velocity = 0 km/h( car stops) and initial velocity = 30 km/h

             So acceleration = (0-30)/time = -30/ time

             Time is always positive , so -30/time is negative, so the stopping car has negative acceleration.

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andrezito [222]

Answer:

centripetal acceleration of the ball is 6.9 m/s/s

tangential speed of the ball is 2.2 m/s

Explanation:

As we know that ball complete 5 rotations in 10 seconds

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4 0
2 years ago
A proton moves a distance 10 cm in a uniform electric field of 3.5 kN C, in the direction of the field.
lawyer [7]

The change in potential energy of the proton is  5.6 x 10^{-17} Joule

<h3>What is a Uniform Electric Field ?</h3>

A uniform electric field is where the electric field strength is the same at all points in the field. In the uniform field, the force experienced by a charge is the same no matter where it is placed in the field.

Given that a proton moves a distance 10 cm in a uniform electric field of 3.5 kN C, in the direction of the field.

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  • Electric field E = 3.5 KN/C
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The Work done = Fd

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Recall that Electric field E = F/q = V/d

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make F the subject of formula and substitute it in work formula

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Work done = Energy = Potential Energy

Therefore, the change in potential energy of the proton is 5.6 x 10^{-17}<em> Joule</em>

<em />

Learn more about Electric Field here: brainly.com/question/14372859

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