Work = (force) x (distance)
The work he did: Work = (700 N) x (4m) = 2,800 joules
The rate at which
he did it (power): Work/time = 2,800 joules/2 sec
= 1,400 joules/sec
= 1,400 watts
= 1.877... horsepower (rounded)
Inelastic collision happens when two objects joined and move together after the collision
Answer:

Explanation:
Average velocity is defined as the ratio of total displacement of the motion and total time taken in that motion
here we know that initially the sky diver drops without opening parachute by total displacement 625 m
then she open her parachute and drop another 362 m
so first it took time t = 15 s to drop without open parachute
then it took t = 139 s to drop next displacement
so here total displacement is given as

total time is given as

so average velocity is given as


Answer:
The electric flux is zero because charge is zero.
Explanation:
Given that,
Positive charge 
Negative charge 
We need to calculate the total charged
Using formula of charge

Put the value into the formula


We need to calculate the electric flux
Using formula of electric flux

Put the value into the formula

Hence, The electric flux is zero because charge is zero.
Answer:
Explanation:
The change is as follows
P₁ V₁ to 3P₁, V₁ ( constt volume ) --- first process
3P₁,V₁ to 3P₁ , 5V₁ ( constt pressure ) ---- second process
In the first process Temperature must have been increased 3 times . So if initial temperature is T₁ then final temperature will be 3 T₁
P₁V₁ = n R T₁ , n is no of moles of gas enclosed.
nRT₁ = P₁V₁
Heat added at constant volume = n Cv ( 3T₁ - T₁)
= n x 5/3 R X 2T₁ ( for diatomic gas Cv = 5/3 R)
= 10/3 x nRT₁
= 10/3x P₁V₁
In the second process, Temperature must have been increased 5 times . So if initial temperature is 3T₁ then final temperature will be 15 T₁
Heat added at constant pressure in second case
= n Cp ( 15T₁ - 3T₁)
= n x 7/3 R X 12T₁ ( For diatomic gas Cp = 7/3 R)
= 28 x nRT₁
= 28 P₁V₁