All categories

4 years ago

Please explain how you got the answer :(

Physics

1 answer:

tensa zangetsu [6.8K]4 years ago

3 0

Answer:

36.5 kJ

Explanation:

Energy by machine = energy to machine × efficiency

E = 52.1 kJ × 0.70

E = 36.5 kJ

You might be interested in

Which of the following refers to stored energy that an object has due to its height?

VLD [36.1K]

Answer : D. Gravitational Potential

Gravitational Potential energy =mgh

5 0

3 years ago

Read 2 more answers

You drop a batitin a stationary elevator and the ball hits the floor in o 50 s. How long does it take for the ball to hit the fl

solmaris [256]

Answer:

option (a) 0.61 s

Explanation:

Given;

Time taken by the ball to reach the ground = 0.50 s

Let us first calculate the distance through which the ball falls on the ground

from the Newton's equation of motion, we have

$s=ut+\frac{1}{2}at^2$

where,

s is the distance

a is the acceleration

t is the time

here it is the case of free fall

thus, a = g = acceleration due to gravity

u = initial speed of the ball = 0

on substituting the values, we get

$s=0\times 0.50+\frac{1}{2}\times9.8\times0.50^2$

s = 1.225 m

Now,

when the elevator is moving up with speed of 1.0 m/s

the initial speed of the ball = -1.0 m/s (as the elevator is moving in upward direction)

thus , we have

$s=ut+\frac{1}{2}at^2$

$1.225=-1.0\times\ t+\frac{1}{2}\times9.8t^2$

4.9t^2 - t - 1.225 = 0

t = 0.612 s

hence, the correct answer is option (a) 0.61 s

4 0

4 years ago

How does changing the voltage in a circuit affect the current in the circuit

Tasya [4]

The formula for the voltage is shown below:
Voltage = Current x Resistance
V=I x R

When we change voltage:
I =V/R or R=V/I
Increasing the voltage in an electrical circuit will also increase the current value, as well as the resistance of the load,

7 0

3 years ago

Read 2 more answers

Bone has a Young's modulus of about

saveliy_v [14]

Answer: 4.74 mm

Explanation:

We can solve this problem with the following equation:

$Y=\frac{stress}{strain}$ (1)

Where:

$Y=1.8(10)^{10} Pa$ is the Young modulus for femur

$stress=\frac{F}{A}=1.58(10)^{8} Pa$ is the stress (force $F$ applied per unit of transversal area $A$ ) on the femur

$strain=\frac{\Delta l}{l_{o}}$

Being:

$\Delta l$ the compression the femur can withstand before breaking

$l_{o}=0.54 m$ is the length of the femur without compression

Writing the data in equation (1):

$Y=\frac{\frac{F}{A}}{\frac{\Delta l}{l_{o}}}$ (2)

$1.8(10)^{10} Pa=\frac{1.58(10)^{8} Pa}{\frac{\Delta l}{0.54 m}}$ (3)

Isolating $\Delta l$ :

$\Delta l=\frac{(1.58(10)^{8} Pa)(0.54 m)}{1.8(10)^{10} Pa}$ (4)

$\Delta l=0.00474 m$ (5) This is the compression in meters

Converting this result to millimeters:

$\Delta l=0.00474 m \frac{1000 mm}{1 m}=4.74 mm$

4 0

4 years ago

1. What are 3 main categories of waste and what is the largest contribution of municipal solid waste?

Tasya [4]

Organic materials continue to be the largest component of MSW. Paper and paperboard account for 27 percent and yard trimmings and food account for another 28 percent. Plastics comprise about 13 percent; metals make up 9 percent; and rubber, leather, and textiles account for 9 percent.

5 0

3 years ago