How much force is needed to make a 60kg object accelerate at a rate of 2.0 m/S2?

A small bulb is rated at 7.5 W when operated at 125 V. The tungsten filament has a temperature coefficient of resistivity α = 0.

alisha [4.7K]

To solve this problem we will apply the concepts related to resistance as a function of temperature, product of the relationship between the squared voltage and the power. Mathematically this is,

$R = \frac{v^2}{P}$

Here,

R = Resistance (At function of temperature)

v = Voltage

P = Power

Then we have,

R at 140°C (7 times room temperature),

$R(140\°C) = \frac{125^2}{7.5}$

$R(140\°C) = 2083.33\Omega$

The relationship between normal temperature and increased temperature would then be given by,

$R(140\°C) = R(20\°C)(1 +\alpha (\Delta T))$

$R(140\°C) = R(20\°C)(1+(4.5*10^{-3})(140-20))$

$R(20\°C) = \frac{2083.33}{1.54}$

$R(20\°C) = 1352.81\Omega$

Therefore the correct value of the group of answer is 1350

5 0

3 years ago

5 ways in which people can explore space without physically <br> going there

goblinko [34]

Telescope
books
drawings
satellites
images taken from rockets

i hope these help and that there right!!

8 0

3 years ago

This type of polarization occurs when a beam of light passes from one material into another material.

Anna007 [38]

A. Refraction
This is because refraction occurs when a beam of light passes from one material into another material.

4 0

3 years ago

Read 2 more answers

Which statement is true about the law of conservation of energy for an object released from a certain height above the ground

gregori [183]

The question is really specific enough, but I will take a guess. If nothing else changes (like the mass or the gravitational constant) then the Potential Energy will increase with an increase in height. Ep will decrease with a decrease in height.

If you are talking about Ke, then the height does not matter unless the object is moving up. Then it slows down. When that happens the Ke decreases because the formula for Ke = 1/2 m v^2. If v becomes less then Ke becomes less.

I suppose you could say if the object is going down and the distance is decreasing then the speed will increase. It's an inverse relationship.

I think you are best talking about Pe.

6 0

4 years ago

Beat frequency problem. Your ear simultaneously hears waves from different sources, so it can hear beats from the two speakers.

podryga [215]

Completed question:Suppose one speaker is driven at 570 Hz and the other at 554 Hz. What is the beat frequency in Hz? The average frequency in Hz?

Answer:

Beat frequency= 16Hz

Average frequency = 562Hz

Explanation:

Beat frequency f = f2-f1

Where f2 is frequency of source with higher frequency

f1 is frequency of source with lower frequency

f1= 554Hz, f2= 570Hz

beat frequency (f) = 570 -554

= 16Hz

Average frequency = $\frac{554+570}{2}$

= $\frac{1124}{2}\\ =562Hz$

5 0

4 years ago