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3 years ago

Physical Science E2020 Unit Test

Physics

2 answers:

mart [117]3 years ago

8 0

Answer:The correct answer is option B.

Explanation:

Work done is defined product of force applied on an object and the displacement of an object on applying of force.It is measured in Joules.

$W=Force\times Displacement$

1. Chet

Work done = $50 N\times 1.0 m= 50.0 Joules$

2. Mika

Work done = $40 N\times 2.0 m= 80.0 Joules$

3. Sara

Work done = $30 N\times 1.5 m= 45.0 Joules$

4.Bill

Work done = $60 N\times 0.5 m= 30.0 Joules$

The greatest work was done by Mika and least work was done by BIll. The order from the greatest amount of work done to the least.

Mika>Chet>Sara>Bill.

Hence ,the correct answer is option B.

vladimir2022 [97]3 years ago

5 0

i think its b

hope this helps

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Setler [38]

Answer:

b. K = U

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Alika [10]

final velocity of a falling object = 0

and acceleration of a falling object is negative

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${u}^{2} \: the \: subject$

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from the question,

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but the question is demanding for time but not the initial velocity

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Newton's first equation of motion

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Dmitry_Shevchenko [17]

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The situation is represented in the picture attached.

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4 years ago

In which of the following cases will the normal force on a box be the greatest? A. When the box is placed in a stationary elevat

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Answer:

D. When the box is placed in an elevator accelerating upward

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3 years ago

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Please, Help!!

Elenna [48]

Let, 1st force = a

2nd force = b

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a+b = 10

a-b = 6

Calculate for a & b, you'll get a=8 & b= 2

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*Physical Science* *E2020* *Unit Test*

Physical Science E2020 Unit Test