Force is the change in momentum over a specific time. The change of momentum is therefore the force multiplied by the time that the force acts, so 3000x4.0=12000 N s=12000 kg m/s
Answer:
The coefficient of kinetic friction is 1.03
Explanation:
<u>Step 1:</u> Given data
⇒ mass of the block = 0.600 kg
⇒ elastic constant k = 20 N/m
⇒ The spring is compressed by 20.0 cm (=x) = 0.2 m
⇒ Once it loses contact with the spring, the block travels a distance 33 cm
<u>Step 2:</u> Calculate the potential energy
Ep = 1/2 * k * x²
Ep = 1/2 * 20N/m * (0.2m)²
Ep = 0.4 Nm
<u>Step 3:</u> Calculate the coefficient of kinetic friction
At the end of the movement Potential energy = work
W = Ep = 0.4Nm = µx * m * g* x
µx = Ep / (m*g*x)
µx = 2Nm / ( 0.6 kg * 9.81 m/s² * 0.33m)
µx = 1.03
The coefficient of kinetic friction is 1.03
When a person is pulled upwards why the motor of the helicopter
Then the potential energy increased of the person is given as
here m = 109 kg
h = 83 m
so here potential energy of the person given as
now power is defined as rate of energy
so it took 55 s to pull the mass so power is given as
now we know that efficiency of motor is given as 69%
so we have
so we have power as