Anyone Can Help Thanx In Advance

Physics anyone? i need help :) thanks in advance?

A couch with a mass of 100 kg is placed on an adjustable ramp connected to a truck. As one end of the ramp is raised, the couch begins to move downward. Is the couch slides down the ramp with an acceleration of .79 m/s squared when the ramp angle is 12 degrees, what is the coefficient of kinetic friction between the ramp and the couch?

Physics HW help. Thanks in advance?

Question 1:

mass of sprinter = 70 kg

AT STARTING BLOCK:

initial velocity of sprinter (u) = 0 m/s
final velocity of sprinter (v) = 5 m/s
Time at starting block (t) = 0.2 s
Acceleration of sprinter at starting block = a

v = u + at
5 = 0.2a
a = 25 m/s^2

Reaction force exerted by block on sprinter = F

F = ma = 70 kg * 25 m/s^2 = 1750 N
Therefore, reaction force of starting block = 1750 N

Average velocity = (v+u)/2 = 2.5 m/s

Average power output at blocks = F * average velocity
= 1750 * 2.5
= 4375 W or 4.375 kW

WHILE RUNNING:

initial velocity (u) = 5 m/s
final velocity (v) = 12 m/s
time = 5 s
Second acceleration = a1

v = u + (a1)t
12 = 5 + 5(a1)
7 = 5(a1)

a1 = 1.4 m/s^2

Therefore, second acceleration of sprinter = 1.4 m/s^2
F = m*a1 = 70 * 1.4 = 98 N

Average velocity = (v+u)/2 = 8.5 m/s

Average power output at 2nd acceleration
= F * average velocity
= 98 * 8.5
= 833 W



Question 2:

mass of stone = m
height of stone = h
gravity acceleration = g = 9.81 m/s^2

Potential energy of stone at full height = mgh
= 3.0 kg * 9.81 m/s^2 * 100m
= 2943 J

Potential energy of stone at 50 m = mgh
= 3.0 kg * 9.81 m/s^2 * 50m
= 1471.5 J

Kinetic energy of stone at 50m = potential energy at full height - potential energy at 50m
= 2943 J - 1471.5 J
= 1471.5 J

Can anyone help me with this question? thanks in advance?

Since the female lays thousands of eggs and the male then sheds millions of sperm over them, there is a greater chance that more will be fertilized than if the female layed, say, 20 eggs, and the male only shed 500 sperm. These large numbers ensure the continuation of the species.

ASTRONOMY 101 HELP! thanks in advance! 1,2, or 3?

I am doing this same homework right now. The first answer is 1) all the planets formed in a rotating, disk-shaped nebula. The second answer 2) this might have happened in our own solar system if it had taken longer for the solar wind to clear the solar nebula.

Can anyone translate this: Amadi Mio? Thanks in advance...?

the other term I use for 'the Bearded One'

Anyone good with physics that could help me?

I could really use any help on this problem that anyone could give me. Thanks in advance. I will give 10 points if anyone can help me out.

A microscope has an objective lens (with a focal length of 16.22 mm and an eyepiece with a focal length of 9.20 mm). With the length of the barrel set at 27.0 cm, the diameter of a red blood cell's image subtends an angle of 1.43 mrad with the eye. If the final image distance is 27.0 cm from the eyepiece, what is the actual diameter of the red blood cell (in µm)?

Can anyone please give me any help with this problem?? thank you so much in advance?

You do realize that different states have different laws and that some of the answers are based on law from their states. As I live in Texas, I will speak from a Texa view. Robert made a good sound decision for his firm He weighed the pros and the cons and decided Michael was no longer an asset but a liability. I would have to check with an attorney but I believe that he could have told Michael that his services were no longer needed in that capacity. Then he could have asked Michael if he had ever considered being in business for himself and then ask him if he was interested in working as a contractor doing the same accounts as before. With a increase in pay. Michael will no longer be getting a pay check from the firm but he will be receiving payments for his service but he has to pay his own social security and insurance. So If I was Robert I would figure how much Michael really earned a month and put in 2 to 3 % more to make it worth it to Michael, both get what they want.