Can someone please help me on this!!!

A rope passes over a fixed sheave with both ends hanging straight down. The coefficient of friction between the rope and sheave

Oliga [24]

Answer:3.51

Explanation:

Given

Coefficient of Friction $\mu =0.4$

Consider a small element at an angle \theta having an angle of $d\theta$

Normal Force $=T\times \frac{d\theta }{2}+(T+dT)\cdot \frac{d\theta }{2}$

$N=T\cdot d\theta$

Friction $f=\mu \times Normal\ Reaction$

$f=\mu \cdot N$

and $T+dT-T=f=\mu Td\theta$

$dT=\mu Td\theta$

$\frac{dT}{T}=\mu d\theta$

$\int_{T_2}^{T_1}\frac{dT}{T}=\int_{0}^{\pi }\mu d\theta$

$\frac{T_2}{T_1}=e^{\mu \pi}$

$\frac{T_2}{T_1}=e^{0.4\times \pi }$

$\frac{T_2}{T_1}==e^{1.256}$

$\frac{T_2}{T_1}=3.51$

7 0

3 years ago

A car radio draws 0.27 A of current in the autos 12-V electrical system. (a) How much electric power does the radio use?

Lostsunrise [7]

Answer:

(a) 3.24 w (b) 44.44 ohm

Explanation:

It is given that car draws 0.27 A current so current I = 0.27 A

The system has a voltage of 12 V

(a) Electrical power = voltage ×current $=12\times 0.27=3.24W$

(b) The resistance is defined as the ratio of voltage and current

So resistance $R=\frac{V}{I}=\frac{12}{0.27}=44.44 ohm$

8 0

3 years ago

State Pascal's principle of transmission of pressure

bulgar [2K]

Answer:

Pascal's law (also Pascal's principle or the principle of transmission of fluid-pressure) is a principle in fluid mechanics given by Blaise Pascal that states that a pressure change at any point in a confined incompressible fluid is transmitted throughout the fluid such that the same change occurs everywhere.

4 0

3 years ago

Voltage needed to raise current to 3.75a using 20,20,200 resistor set

Varvara68 [4.7K]

Answer: The voltage needed is 35.7 V

Explanation:

Assuming that the resistors are arranged in parallel combination.

For the resistors arranged in parallel combination:

$\frac{1}{R}=\frac{1}{R_1}+\frac{1}{R_2}+\frac{1}{R_3}$

We are given:

$R_1=20\Omega\\R_2=20\Omega\\R_3=200\Omega$

Using above equation, we get:

$\frac{1}{R}=\frac{1}{20}+\frac{1}{20}+\frac{1}{200}\\\\\frac{1}{R}=\frac{10+10+1}{200}\\\\R=\frac{200}{21}=9.52\Omega$

Calculating the voltage by using Ohm's law:

$V=IR$ .....(1)

where,

V = voltage applied

I = Current = 3.75 A

R = Resistance = $9.52\Omega$

Putting values in equation 1, we get:

$V=3.75\times 9.52\\\\V=35.7V$

Hence, the voltage needed is 35.7 V

7 0

3 years ago

Read 2 more answers

Choose the answer choice that BEST completes the following sentence. About four million tons of __________________ are converted

yaroslaw [1]

Answer:

About four million tons of matter are converted to energy in the Sun’s core every second

Explanation:

The Sun

It's estimated that The Sun fuses near 600 million tons $(6.10^9\ kg)$ of hydrogen into helium every second. As a result, 4 million tons of matter are converted to energy every second according to Einstein's equation $E=mc^2$

4 0

3 years ago