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3 years ago

5) A person holds a 1.7 kg bucket and lets it move down at

Physics

1 answer:

Elena L [17]3 years ago

7 0

Answer:

12.5J

Explanation:

Given parameters:

Mass of bucket = 1.7kg

Height = 75cm = 0.75m

Unknown;

Work done on the bucket by the person = ?

Solution:

To solve this problem, we use the work done equation;

Work done = force x distance = mgh

m is the mass

g is the acceleration due to gravity

h is the height

Now, insert parameters and solve ;

Work done = 1.7 x 9.8 x 0.75 = 12.5J

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The elastic energy stored in your tendons can contribute up to 35 % of your energy needs when running. Sports scientists have st

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Complete Question:

The elastic energy stored in your tendons can contribute up to 35 % of your energy needs when running. Sports scientists have studied the change in length of the knee extensor tendon in sprinters and nonathletes. They find (on average) that the sprinters' tendons stretch 43 mm , while nonathletes' stretch only 32 mm . The spring constant for the tendon is the same for both groups, $31 {\rm {N}/{mm}}$ . What is the difference in maximum stored energy between the sprinters and the nonathlethes?

Answer:

$\triangle E = 12.79 J$

Explanation:

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Difference in maximum stored energy between the sprinters and the non-athlethes:

$\triangle E = E_s - E_n = 0.5k(x_s^2 - x_n^2)\\\triangle E = 0.5*3100* (0.043^2 - 0.032^2)\\\triangle E = 0.5*31000*0.000825\\\triangle E = 12.79 J$

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3 years ago

The one invention that has made many complex machines possible is the invention of the:

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3 years ago

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RideAnS [48]

Answer:

The correct option is B. 7.5 * 10¹⁴ Hz

Explanation:

Frequency = (speed) / (wavelength)

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= (0.75 x 10¹⁵) /sec

= 7.5 x 10¹⁴ Hz

= 750,000 GHz

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2 years ago

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