All categories

4 years ago

John stretched while his muscles were cold. Which negative effect could occur?

Physics

2 answers:

Ede4ka [16]4 years ago

5 0

Answer:

The answer for Plato is C.

Genrish500 [490]4 years ago

3 0

<h3>Answer;</h3>

C) He could injure or pull a muscle.

<h3>Explanation;</h3>

When muscles are stretched the muscle fibers are temporary lengthened. Muscles have a unique ability to undergo contraction and lengthening since they are elastic.
When the muscles are warm they are more elastic, therefore, warming up the muscles is very important for the purpose of avoiding injuries. Ir is important to engage in moderate cardiovascular warm-up prior to stretching, which increases the blood flow to the active and thus avoiding injuries to the muscles.
Stretching muscles when they are cold may bring injuries or cause muscle pulls, which are painful.

You might be interested in

22) How many moles of NaCl (table salt) are there in 1600 gram sample?

arlik [135]

Answer:

16400.........................

3 0

3 years ago

The block in the drawing has dimensions L0×2L0×3L0,where L0 =0.5 m. The block has a thermal conductivity of 200 J/(s·m·C˚). In d

Dennis_Churaev [7]

Answer:

$Q_p=18000\ J$

$Q_o=8000\ J$

$Q_g=72000\ J$

Explanation:

Given:

Length of block, $l=3L_o=3\times 0.5=1.5\ m$

Breadth of block, $b=L_o=0.5\ m$

height of block, $h=2L_o=2\times 0.5=1\ m$

Thermal conductivity of the block, $k=200\ W.m.^{\circ}C$

Temperature on the hotter side, $T_H=37^{\circ}C$

temperature on the cooler side, $T_L=7^{\circ}C$

time for which the heat flows, $t=4\ s$

REFER THE ATTACHED IMAGE FOR THE REFERENCE

The rate of heat flow using Fourier's law of conduction is given as:

$\frac{Q}{t}=k.A.\frac{dT}{dx}$

Now the amount heat flow perpendicular to the pink surface:

$\frac{Q_p}{4}=200\times (0.5\times 1.5).\frac{30}{1}$

$Q_p=18000\ J$

Now the amount heat flow perpendicular to the orange surface:

$\frac{Q_o}{4}=200\times (0.5\times 1).\frac{30}{1.5}$

$Q_o=8000\ J$

Now the amount heat flow perpendicular to the green surface:

$\frac{Q_g}{4}=200\times (1.5\times 1).\frac{30}{0.5}$

$Q_g=72000\ J$

6 0

4 years ago

Three fire hoses are connected to a fire hydrant. Each hose has a radius of 0.017 m. Water enters the hydrant through an undergr

alexira [117]

Answer:

2.36 x 10^5 kg

Explanation:

radius of hose, r = 0.017 m

radius of underground pipe, R = 0.088 m

number of hoses, n = 3

velocity of water in underground pipe, V = 2.7 m/s

Let v is the velocity of water in each hose.

According to the equation of continuity

A x V = n x a x v

π R² x V = n x π x r² x v

0.088 x 0.088 x 2.7 = 3 x 0.017 x 0.017 x v

v = 24.12 m/s

(a) Amount of water poured onto a fire in one hour by all the three hoses

= n x a x v x density of water x time

= 3 x 3.14 x 0.017 x 0.017 x 24.12 x 1000 x 3600

= 2.36 x 10^5 kg

Thus, the amount of water poured onto the fire in one hour is 2.36 x 10^5 kg.

6 0

3 years ago

Five equal negative charges are uniformly spaced in a semicircular

balu736 [363]

Answer:

The direction is that of a 3rd quadrant angle

Explanation:

when you have 2 45 angles it equals to 90 then with the 90 we multiply by 2 due to the 2 adjacent angles equating to 180 which swings it to the 3rd quadrant angle

6 0

4 years ago

A lawn sprinkler sprays water 8 feet at full pressure as it rotates 360 degrees. if the water pressure is reduced by 50%, what i

lina2011 [118]

The area of the sprinkles can be determined through the area of a circle that is pi * r^2 in which the given dimensions above are the radii, r. The second scenarios radius is only half of the original, that is 4 ft. In this case, we can compute the area of the second again. We calculate next the difference of two areas of circles.

7 0

4 years ago