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3 years ago

The weightlifter's internal store of energy decreased when he lifted the bar.

Physics

1 answer:

Mumz [18]3 years ago

5 0

Answer:

The energy returns to the weightlifter's muscles, where it is dissipated as heat.

Explanation:

The energy returns to the weightlifter's muscles, where it is dissipated as heat. As long as the weightlifter controls the weight's descent, their muscles are acting as an overdamped shock absorber, as if the weight were sitting on a piston containing very thick fluid, slowly compressing it downward (and slightly heating up the fluid in the process). Since muscles are complicated biological systems and not simple pistons, they require metabolic energy to maintain tension throughout the controlled descent, so the weightlifter feels like they're putting energy into the weight, even though the weight's gravitational potential energy is being converted into heat within the lifter's muscles.

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10) If the mass 2m, the left mass

Romashka-Z-Leto [24]

Answer:

F = $\frac{-Gm_{1}m_{2} }{r^{2} }$ .

Explanation:

Gravitational force between two objects of masses $m_{1}, m_{2}$ kept at a distance r is given by the formula

F = $\frac{-Gm_{1}m_{2} }{r^{2} }$

Here , $m_{1}$ = 2m

$m_{2}$ = $\frac{m}{2}$

Thus , F = $\frac{-G.2m.\frac{m}{2} }{r^{2} }$

F = $\frac{-Gm_{1}m_{2} }{r^{2} }$ .

7 0

3 years ago

Which of the following is not a step in the inquiry process

padilas [110]

"The process used by scientific investigations is the scientific method. This involves making an observation, stating a question, formulating a hypothesis, conducting an experiment and analyzing the results to form a conclusion. "

I would most likely go with B. but im not 100% sure

8 0

4 years ago

Label and describe what is happening in this picture

SOVA2 [1]

Something is reproducing.

7 0

3 years ago

A double-slit experiment yields an interference pattern due to the path length difference from light traveling through one slit

Lapatulllka [165]

Answer:

Therefore the correct statement is B.

Explanation:

In the interference and diffraction phenomena, the natural wave of electromagnetic radiation must be taken into account, the wave front that advances towards the slit can be considered as when it reaches it behaves like a series of wave emitters, each slightly out of phase from the previous one, following the Huygens principle that states that each point is compiled as a source of secondary waves.

The sum of all these waves results in the diffraction curve of the slit that has the shape

I = Io sin² θ /θ²

Where the angle is a function of the wavelength and the width of the slit.

From the above, the interference phenomenon can be treated as the sum of two diffraction phenomena displaced a distance equal to the separation of the slits (d)

Therefore the correct statement is B

6 0

3 years ago

A rubber balloon is filled with 1 L of air at 1 atm and 300 K and is then put into a cryogenic refrigerator at 100 K. The rubber

Kipish [7]

Answer:

The correct answers are

(a) It decreases to 1/3 L

(ii) is (c) It is constant

Explanation:

to solve this, we list out the number of knowns and unknowns so as to determine the correct equation to solve the problem

The given variables are as follows

Initial volume V1 = 1L

V2 = Unknown

Initial Temperature T1 = 300K

let us assume that the balloon is perfectly elastic

At 300K the balloon is filled and it stretches to maintain 1 atmosphere

at 100K the content of the balloon cools reducing the excitement of the gas content which also reduces the pressure, however, the balloon being perfectly elastic, contracts to maintain the 1 atmospheric pressure, hence the answer to (ii) is (c) It is constant,

For (i) since we know that the pressure of the balloon is constant

by Charles Law V1/T1 =V2/T2

or V2 = (V1/T1)×T2 = $\frac{1L}{300K}$ × $100K$ = $\frac{1}{3}$ × L = L/3 hence the correct answer to (i) is 1/3L

8 0

3 years ago