Answer:
The kinetic energy is: 50[J]
Explanation:
The ball is having a potential energy of 100 [J], therefore
PE = [J]
The elevation is 10 [m], and at this point the ball is having only potential energy, the kinetic energy is zero.
![E_{p} =m*g*h\\where:\\g= gravity[m/s^{2} ]\\m = mass [kg]\\m= \frac{E_{p} }{g*h}\\ m= \frac{100}{9.81*10}\\\\m= 1.01[kg]\\\\](https://tex.z-dn.net/?f=E_%7Bp%7D%20%3Dm%2Ag%2Ah%5C%5Cwhere%3A%5C%5Cg%3D%20gravity%5Bm%2Fs%5E%7B2%7D%20%5D%5C%5Cm%20%3D%20mass%20%5Bkg%5D%5C%5Cm%3D%20%5Cfrac%7BE_%7Bp%7D%20%7D%7Bg%2Ah%7D%5C%5C%20m%3D%20%5Cfrac%7B100%7D%7B9.81%2A10%7D%5C%5C%5C%5Cm%3D%201.01%5Bkg%5D%5C%5C%5C%5C)
In the moment when the ball starts to fall, it will lose potential energy and the potential energy will be transforme in kinetic energy.
When the elevation is 5 [m], we have a potential energy of
![P_{e} =m*g*h\\P_{e} =1.01*9.81*5\\\\P_{e} = 50 [J]\\](https://tex.z-dn.net/?f=P_%7Be%7D%20%3Dm%2Ag%2Ah%5C%5CP_%7Be%7D%20%3D1.01%2A9.81%2A5%5C%5C%5C%5CP_%7Be%7D%20%3D%2050%20%5BJ%5D%5C%5C)
This energy is equal to the kinetic energy, therefore
Ke= 50 [J]
Answer:

Explanation:
Let the total force be F
The force that produces motion in the x direction is given as, 
Let the frictional force be given as:

Thus, the net force is given as:

Left. Opposite of the direction the box is pushed.
As the water boils at a certain temperature, phase change happen without change in its temperature. The heat associated is called the latent heat of vaporization. We obtain the heat required by multiplying the mass of the water to the latent heat of vaporization.
Heat = 0.018 x <span>2.3 x 10000000 = 41400 J</span>
Answer:
Length of the arc of this sector, l = 14 cm
Explanation:
It is given that, the perimeter of a sector of a circle is the sum of the two sides formed by the radii and the length of the included arc.
Perimeter of sector, P = 28 cm
Area of sector, 
According to figure,
2r + l = 28 ............(1)
Area of sector, 
Where,
is in radian and 
Since, 


Put the value of r in equation (1) so,


On solving above equation for l we get, l = 14 cm. So, the length of the arc of this sector is 14 cm. Hence, this is the required solution.