Power is the work performed divided by time in seconds. The work is the force times distance:
the time in seconds is 60*11+30=690s so the power is
So choice B
Answer:
The acceleration of the total mass decreases by half (1/2)
Explanation:
Given;
acceleration of sled = 2 m/s²
From Newton's second law of motion, F = ma
⇒m = F/a
F is the force applied by Jenny
This force applied by Jenny should be the same, after Tommy jumps on the sled, but the acceleration will change.
F = m₁a₁ = m₂a₂
Since m₂ = 2m₁, then we calculate a₂
m₁a₁ = 2m₁a₂
a₂ = a₁/2
Therefore,The acceleration of the total mass decreases by half.
There's no possible way to think about the validity of that equation until we know what the variables v, R, and g represent.
The third hour was positive acceleration and the second hour was negative acceleration
