Answer: 5.31 meters
Explanation: Use conservation of energy. Initial energy equals final energy. Initially, there is only kinetic energy (because height = 0 initially). At the end, kinetic energy equals 0 because at max height, there is max potential energy and the ball stops moving for a split second.
mgh = .5mv^2
Masses cancel out
gh = .5v^2
(9.8)(h) = .5(10.2^2)
Solve for h. h = 5.31 meters
Answer: 4.9 x 10^6 joules
Explanation:
Given that:
mass of boulder (m) = 2,500 kg
Height of ledge above canyon floor (h) = 200 m
Gravita-tional potential energy of the boulder (GPE) = ?
Since potential energy is the energy possessed by a body at rest, and it depends on the mass of the object (m), gravitational acceleration (g), and height (h).
GPE = mgh
GPE = 2500kg x 9.8m/s2 x 200m
GPE = 4900000J
Place result in standard form
GPE = 4.9 x 10^6J
Thus, the gravita-tional potential energy of the boulder-Earth system relative to the canyon floor is 4.9 x 10^6 joules
Explanation:
It is given that,
Mass of the football player, m = 92 kg
Velocity of player, v = 5 m/s
Time taken, t = 10 s
(1) We need to find the original kinetic energy of the player. It is given by :


k = 1150 J
In two significant figure, 
(2) We know that work done is equal to the change in kinetic energy. Work done per unit time is called power of the player. We need to find the average power required to stop him. So, his final velocity v = 0
i.e. 

P = 115 watts
In two significant figures, 
Hence, this is the required solution.
Answer:
The answer is D. A Vacumn
Explanation:
Sound cannot travel through a vacuum. A vacuum is an area without any air, like space. So sound cannot travel through space because there is no matter for the vibrations to work in.
Answer:
The value is 
Explanation:
From the question we are told that
The wavelength is 
The distance is of the screen is 
The width of the fifth dark spot is 
Generally the width of a fringe is mathematically represented as

=> 
=> 
=> 