Yes it does, uh huh. It slows down as it rolls. That's a fact.
In order for the ball to roll forward, it has to push grass out of the way. That takes energy. To bend each blade of grass out of its way, the ball has to use a tiny bit of the kinetic energy that it has, so it gradually runs out of kinetic energy. When its kinetic energy is all gone, it stops moving.
Because the core is a big ball of iron
Answer:
U = 8.30×10-⁹J
Explanation:
m1 = m2 = 5.00kg masses of the spheres
d = 15.0cm = 15×10-²m
r = 5.10cm = 5.10×10-²m
R = d + r = 15×10-² + 5.10×10-²
R = 20.10 ×10-²m = 0.201m
G = 6.67×10-¹¹Nm²/kg²
U = Gm1×m2/R = potential energybetween the spheres
U = 6.67×10-¹¹×5.00×5.00/0.201
U = 8.30×10-⁹J
Answer:
The statement is true: velocity and acceleration have opposite directions in the interval of braking.
Explanation:
Let's say we have a velocity 
.
The acceleration 
is the rate of change of the velocity 
. This means that if is <em>increasing during</em> time, then must be positive. But if is <em>decreasing over</em> time, then will be negative (even though the velocity is positive).
Mathematically:
decreases ⇒
⇒
.
Example:
