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BARSIC [14]
3 years ago
6

. A child pulls a sled up a snow-covered hill. In the process, the child does 405 J of work on the sled. If she walks a distance

of 15 m up the hill, how large a force does she exert on the sled?
Physics
1 answer:
leonid [27]3 years ago
5 0
<span>Work done by child W = 405 J; Distance walked s = 15 m
 Calculating the force exerted on the sled,
 Work = Force x distance
 => Force F = Work W / distance s => => F = 405 / 15 = 27 N
 Force F is 27 Newtons.</span>
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mart [117]
<h3><u>Answer;</u></h3>

Radius = 0.0818 m

Angular velocity = 2.775 × 10^7 rad/sec

<h3><u>Explanation;</u></h3>

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                          = 2.7 × 10^6 × 1.602 × 10^-19 J;

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Angular velocity, ω = v/r

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  r = 0.0818 m

Angular speed

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3 0
3 years ago
How much heat is needed to bring 12.0 g of water from 28.3 °C to 43.87 °C, if the specific heat capacity of water is 4.184 J/(g•
Vika [28.1K]

Answer:

Heat capacity, Q = 781.74 Joules

Explanation:

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Heat capacity is given by the formula;

Q = mcdt

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Q represents the heat capacity or quantity of heat.

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c represents the specific heat capacity of water.

dt represents the change in temperature.

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7 0
3 years ago
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8 0
3 years ago
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