All categories

2 years ago

Increasing the # of pulleys increases the _ but decreases the amount of applied

Physics

1 answer:

Maksim231197 [3]2 years ago

8 0

Distance, Force

<u>Explanation:</u>

1) Increasing the load will add to the friction on the bearings of the pulleys, thus reducing the efficiency of the system. The ideal mechanical advantage won't change since the ideal mechanical advantage ignores friction.

2) Increasing the number of pulleys will increase the ideal mechanical advantage, but because of friction it will decrease the efficiency. The more pulleys that are turning, the more friction there is, and the less efficient the system will be.

3) Work = force x distance, and what machines do is alter the amount of force you can apply while at the same time reducing the distance moved by the same factor. For instance, a jack multiplies the force you apply by a factor of 100, when you push down on the handle of the jack 100 cm, the car will only go up 1 cm. So the force x distance is the same 100 x force x 1/100 x distance.

You might be interested in

The wheel of a stationary exercise bicycle at your gym makes one rotation in 0.670 s. Consider two points on this wheel: Point P

lesya [120]

Answer:

a) For P: $v=0.938\frac{m}{s}$

For Q: $v = 1.876\frac{m}{s}$

b) For P:

$a_{rad}=8.80\frac{m}{s^{2}}$

for Q:

$a_{rad}=17.60\frac{m}{s^{2}}$

c) As the distance from the axis increases then speed increases too.

Explanation:

a) Assuming constant angular acceleration we can find the angular speed of the wheel dividing the angular displacement θ between time of rotation:

$\omega =\frac{\theta}{t}$

One rotation is 360 degrees or 2π radians, so θ=2π

$\omega =\frac{2\pi}{0.670} =9.38\frac{rad}{s}$

Angular acceleration is at every point on the wheel, but speed (tangential speed) is different and depends on the position (R) respect the rotation axis, the equation that relates angular speed and speed is:

$v = \omega R$

for P:

$v = 9.38\frac{rad}{s}*0.1m=0.938\frac{m}{s}$

for Q:

$v = 9.38\frac{rad}{s}*0.2m=1.876\frac{m}{s}$

b) Centripetal acceleration is:

$a_{rad}= \frac{v^2}{R}$

for P:

$a_{rad}= \frac{(0.938)^2}{0.1}=8.80\frac{m}{s^{2}}$

for Q:

$a_{rad}= \frac{(1.876)^2}{0.2}=17.60\frac{m}{s^{2}}$

c) As seen on a) speed and distance from axis is $v = \omega R$ because ω is constant the if R increases then v increases too.

3 0

3 years ago

What is the frequency of microwaves of wavelength 3 cm?

tiny-mole [99]

Answer:

10 GHz

Explanation:

Applying,

v = λf.................... Equation 1

Where v = speed of microwave, λ = wavelength, f = frequency.

make f the subject of the equation

f = v/λ................ Equation 2

Note: Microwave is an electromagnetic wave, and all electromagnetic wave have the same speed, which is 3×10⁸ m/s

From the question,

Given: λ = 3 cm = 0.03 m

Constant; v = 3×10⁸ m/s

Substitute these values into equation 2

f = 3×10⁸/(0.03)

f = 10¹⁰ Hz

f = (10¹⁰/10⁹) GHz

f = 10 GHz

4 0

2 years ago

Help with 5 and the question below. BRAINLIEST FOR THE CORRECT ANSWER! Urgent Physics help!

krok68 [10]

Sound level at distance of 15 m is given as 20 dB

so intensity at this distance is given as

$L = 10 Log\frac{I}{I_0}$

$20 = 10 Log{I}{10^{-12}}$

$I_1 = 10^{-10}W/m^2$

now if we move closer to some some distance the sound level is now 50 dB

now the intensity is given as

$L = 10 Log\frac{I}{I_0}$

$50 = 10Log\frac{I}{10^{-12}}$

$I_2 = 10^{-7}W/m^2$

now we know that

$\frac{I_1}{I_2} = \frac{r_2^2}{r_1^2}$

$\frac{10^{-10}}{10^{-7}} = \frac{r_2^2}{15^2}$

$r_2 = 47 cm$

so now the distance from friend must be 47 cm

8 0

2 years ago

A string is stretched between a fixed support and a pulley a distance 111 cm apart. The tension on the string is controlled by a

kvv77 [185]

Answer:

88.8 m/s= Speed of wave propagation in the required mode.(3 loops)

Explanation:

When there are 3 loops.

the total length = L = 3 λ /2

⇒ λ = 2 L / 3 = 2 ( 1.11 ) / 3 = 0.74 m

Velocity = v = f λ = (120)(0.74) = 88.8 m/s

3 0

3 years ago

What property or properties of a wave determine it's speed?

mash [69]

The properties of the wave don't determine its speed. The properties of the medium do. You can FIND the speed by measuring the wave's frequency and wavelength.

7 0

3 years ago

Increasing the # of pulleys increases the _______ but decreases the amount of ______ applied

Increasing the # of pulleys increases the _ but decreases the amount of applied