Energy is the ability to do work.<span />
Answer:
s = 23.72 m
v = 21.56 m/s²
Explanation:
given
time to reach the ground (t) = 2.2 second
we know that
a) s = u t + 0.5 g t²
u = 0 m/s
g = 9.8 m/s²
s = 0 + 0.5 × 9.8 × 2.2²
s = 23.72 m
b) impact velocity
v = √(2gh)
v = √(2× 9.8 × 23.72)
v = √464.912
v = 21.56 m/s²
Answer:
e. TA>T>Tc
Explanation:
a) In this case, we cannot say for sure QA>QB>QC. This is because the magnitude of the heat flow will depend on the specific heat and the mass of each sample. Due to the equation:

if we did an energy balance of the system, we would get that>
QA+QB+QC=0
For this equation to be true, at least one of the heats must be negative. And one of the heats must be positive.
We don't know either of them, so we cannot determine if this statement is true.
b) We can say for sure that QA<0, because when the two samples get to equilibrum, the temperatrue of A must be smaller than its original temperature. Therefore, it must have lost heat. But we cannot say for sure if QB<0 because sample B could have gained or lost heat during the process, this will depend on the equilibrium temperature, which we don't know. So we cannot say for sure this option is correct.
c) In this case we don't know for sure if the equilibrium temperature will be greater or smaller than TB. This will depend on the mass and specific heat of the samples, just line in part a.
d) is not complete
e) We know for sure that A must have lost heat, so its equilibrium temperature must be smaller than it's original temperature. We know that C must have gained heat, therefore it's equilibrium temperature must be greater than it's original temperature, so TA>T>Tc must be true.
Answer:
s=vt2 just simplify all into metric units first
Answer:
The resistance of the wire after it is stretched is 93.31R.
Explanation:
Resistance is the property of the material to oppose the current flow through it. It is given by the relation :
R = (ρl)/A
Here ρ is resistivity, l is length of wire and A is the area of the wire.
Let l₀, and A₀ are the original length and original circular cross section area of the wire. while l₁ and A₁ are the new length and new circular cross section area of the wire.
Volume of the original wire, V₀ = A₀ x l₀
Volume of the new wire, V₁ = A₁ x l₁
According to the problem. volume remain same. So,
V₀ = V₁
A₀ x l₀ = A₁ x l₁
It is given that l₁ = 9.66 x l₀. Substitute this value in the above equation;
A₀ x l₀ = A₁ x 9.66 x l₀
A₁ = A₀/9.66
Resistance of the original wire, R = (ρl₀)/A₀
Resistance of the new wire, R₁ = (ρl₁)/A₁
Substitute the value of l₁ and A₁ in the above equation.
R₁ = (ρ x l₀ x 9.66)/(A₀/9.66) = 93.31 x (ρl₀)/A₀
But (ρl₀)/A₀ = R. hence,
R₁ = 93.31 R