Question

what is the power output needed from a motor to lift in the absence of friction a mass of 1.5 ×10⁴ kg 25 m in 6.0 s at constant speed​

Answer 1

The power output needed from a motor to lift a mass in the absence of friction is 0 W, as there is no work being done. The force required to lift the mass can be calculated using Newton's second law, which in this case is 0 N. Therefore, no power is needed.

Step-by-step explanation:

To calculate the power output needed from a motor to lift a mass, we can use the formula:

Power = Work / Time

Work is equal to the force applied on the mass multiplied by the distance it is lifted:

Work = Force x Distance

From the given information, we know that the mass is 1.5 ×10⁴ kg, the distance is 25 m, and the time is 6.0 s. We need to find the force first, which can be calculated using Newton's second law:

Force = mass x acceleration

In this case, since the mass is being lifted at a constant speed, the acceleration is 0 m/s². Therefore, the force is also 0 N, and the power output needed from the motor is also 0 W, as there is no work being done in the absence of friction.

Answer 2

the power output needed is 61.25 × 10⁴

Step-by-step explanation:

The computation of the power output needed is shown below;

Given that

m = 1.5 ×10⁴ kg

v = 25m ÷ 6.0 s

And g = 9.8 m/sec^2

Now based on the above information

p = f × v

= mg × v

= 1.5 ×10⁴ × 9.8 × 25 ÷ 6

= 61.25 × 10⁴

Hence, the power output needed is 61.25 × 10⁴