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3 years ago

30 points! Please answer at least one and how you found it! :)

Physics

1 answer:

const2013 [10]3 years ago

6 0

1 Is advantage because with out is. you couldn't carry the piano at all.
2 Efficiency because it is going against you.

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A Ping-Pong ball has a mass of 2.3 g and a terminal speed of 9.3 m/s. The drag force is of the form bv2 What is the value of b?

Fed [463]

Answer:

The value is $b = 0.00026 \ kg / m$

Explanation:

From the question we are told that

The mass of the Ping-Pong is $m = 2.3 \ g = 0.0023 \ kg$

The terminal speed is $v = 9.3 \ m/s$

The drag force is $bv^2$

Generally the resultant force on the Ping- Pong is mathematically represented as

$F = mg - bv^2$

when terminal velocity is attained , the resultant force is zero so

$0 = mg - bv^2$

=> $b = \frac{m * g}{v^2}$

=> $b = \frac{0.0023 * 9.8}{ 9.3 ^2}$

=> $b = 0.00026 \ kg / m$

6 0

3 years ago

A wrecking ball of mass 500 kg hangs form a crane by a cable of length 25 mit

Ne4ueva [31]

Given :

A wrecking ball of mass 500 kg hangs form a crane by a cable of length 25 m

this wrecking ball is released from an angle of 40 degrees.

To Find :

The height from the lowest point of the arc.

Solution :

From the attached image we have to find the value of h.

So,

$cos \ 40^o = \dfrac{L-h}{L}\\\\0.76=\dfrac{25-h}{25}\\\\h = 25( 1- 0.76)\\\\h = 6 \ m$

Hence, this is the required solution.

5 0

3 years ago

The temperature of an object can be raised by adding _________ or doing _________ on a system.

Nookie1986 [14]

D is the answer because you cause heat by exerting energy

7 0

4 years ago

A piece of Nichrome wire has a radius of 6.5 104 m. It is used in a laboratory to make a heater that uses 4.00 102 W of power wh

Delvig [45]

Answer:

$L=4.8*10^{17}m$

Explanation:

Given data

Power P=4.00×10²W

Radius r=6.5×10⁴m

Voltage V=120V

To find

Length of wire L

Solution

We know that resistance of wire can be obtained from

$P=\frac{V_{2}}{R}\\ R=\frac{V_{2}}{P}$

We also know that R=pL/A solving the length noting that A=πr²

and using p=100×10⁻⁸Ω.m we find that

$L=\frac{RA}{p}\\ L=\frac{\frac{(V^{2})}{P}(\pi r^{2}) }{p} \\L=\frac{V^{2}(\pi r^{2})}{pP}\\ L=\frac{(120V)^{2}\pi (6.5*10^{4} m)^{2} }{100*10^{-8}(4.00*10^{2} W) }\\ L=4.8*10^{17}m$

6 0

3 years ago

I can raise a bucket of cement mix of mass 12kg through a vertical height of 8m in 10 seconds.Calculate the average power used i

Andrei [34K]

Explanation:

Power = work / time

Power = force × distance / time

P = (12 kg × 10 m/s²) (8 m) / (10 s)

P = 96 Watts

5 0

3 years ago