The direction is the same as the direction the ball is moving in. Because of the rolling of the ball, the direction of movement of the surface of the ball is opposite the overall direction of the ball. Since friction will oppose the direction of movement of the surface of the ball, it is in the same direction as the net direction of movement of the ball.
So i believe is exercise:)
Answer:
N = 3.54 * 10²³ atoms
Explanation:
The formula to apply here is the idea gas law;
PV = nRT where ;
P= pressure of the gas= 1.013 * 10⁵ Pa
V= volume of the gas = 4/3 * 3.14 *0.15³= 0.01414 m³
n= amount of a substance = ?
R= ideal gas constant= 8.314
T= temperature= 293 K
Applying the values to the formula;
PV = nRT
1.013 * 10⁵ * 0.01414 = n * 8.314*293
n= 1.013 * 10⁵ * 0.01414 / 8.314*293
n= 0.588 moles
1 mole = 6.022 * 10²⁷ atoms/ mole
0.588 moles = 0.588 * 6.022 * 10²⁷
N = 3.54 * 10²³ atoms