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almond37 [142]
3 years ago
12

A truck is moving with a certain uniform velocity. It is accelerated uniformly by 0.75 m/s^2. After 20 seconds , the velocity be

comes 72km/h.Find the initial velocity
Physics
1 answer:
scoundrel [369]3 years ago
5 0

Answer:

Vi = 5 m/s

Explanation:

let (a) acceleration = 0.75 m/s²

(t) time = 20 seconds

Vf = final velocity = 72 km/hr  (convert to m/s to units consistency = 20 m/s)

find Initial velocity (Vi)

       Vf - Vi

a =  -----------

             t

Vi = Vf - (a * t)  = 20 - (0.75 * 20)

Vi = 5 m/s

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3 years ago
A jewellery melts 500g of Silver to pour into a mould. Calculate how much energy was released as the silver solidified.
irga5000 [103]

When silver is poured into the mould the it will solidify

In this process the phase of the Silver block will change from liquid to solid.

This phase change will lead to release in heat and this heat is known as latent heat of fusion.

The formula to find the latent heat of fusion is given as

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here given that

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now we can find the heat released

Q = 0.5 * 111 kJ

Q = 55.5 kJ

So it will release total heat of 55.5 kJ when it will solidify

8 0
3 years ago
At what altitude above the earth's surface would the acceleration due to gravity be 4.9 m/s^2? Assume the mean radius of the ear
Mandarinka [93]
We apply the gravity calculation expressed in the formula: g=GM/r2 
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Gravity 8m/s2 will be at 658 kms from surface of earth.
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3 years ago
Rahul wants to change the motion map shown so that it shows uniform circular motion. What change should Rahul make?
saw5 [17]

Answer:

B. He should change the lengths of the vectors that point tangent to the circle so that each is the same length.

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3 years ago
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The answers to the respiratory questions are listed below:

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A respiratory system is a biological system found in both plants and animals, which includes organs and structures used for exchanging gas between the organisms and its environments.

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In conclusion, the respiratory system is one that is very important to understand.

Learn more about respiratory system : brainly.com/question/1270124

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