watts = work per second.
work is mgh = 3x10x50=1500
watts out = 1500
Watts used = 2000
eff=1500/2000=75%
It's been a while since I've studied this, but my answers would be:
13. 5730 years. The half-life of a substance is the amount of time it takes for half of it to decay, and, according to the graph, half of the substance remained at 5730 years.
14. 10740 years. According to the graph, only 25% of the carbon remained after 10740 years.
15. 15 atoms. According to the graph, only 12.5% of the carbon remained after 16110 years. 12.5% of 120 atoms is 15 atoms.
16. 1600 atoms. According to the graph, if a sample of carbon is 10740 years old, only 25% of it remains. To find the original amount, multiply the current amount by (100% / 25%), which equals 4. So, 4. 400 atoms * 4 = 1600 atoms is the original amount.
Answer:
The extension of the second wire is 
Explanation:
From the question we are told that
The length of the wire is 
The elongation of the wire is 
The tension is 
The length of the second wire is 
Generally the Young's modulus(Y) of this material is
Where 
Where A is the area which is evaluated as
and 
So
Since the wire are of the same material Young's modulus(Y) is constant
So we have
Now the ration between the first and the second wire is
Since tension , radius are constant
We have
substituting values
Answer:
48.6°
Explanation:
The forward force, F equals the component of the weight along the slope.
So mgsinθ = ma where a = acceleration and θ = angle between the slope and the horizontal.
So a = gsinθ
Since we are given that a = 75%g = 0.75g,
0.75g = gsinθ
sinθ = 0.75
θ = sin⁻¹(0.75)
= 48.6°
Answer: you cant see sound waves but youcan defiently hear them . when the travle through difrent levels they depend on how loud the sound wave is if you hear a loud sound its called a loud sound wave
Explanation:
