Answer:
25N
Explanation:
Given parameters:
Power of the motor = 125W
Average speed = 5m/s
Unknown:
Force supplied to the motor = ?
Solution:
Work done is the force applied to move a body through a particular distance;
Work done = Force x distance
Also,
Work done = Power x time
So;
Force x distance = Power x time
since force is the unknown;
Force =
Speed =
Force =
Now solve;
Force = = 25N
Answer:
the power that must be supplied to the motor is 101.45 hp
Explanation:
Given that,
The weight of elevator = 1000lb
The motor exerts a constant force of 500 lb on the cable
The load has been hoisted s = 15 ft starting from rest
The motor has an efficiency of e = 0.65
According to the equation of motion:
F = ma
To calculate the output power:
P(out) = F. v
P(out) = 3 (500) * 21.98
P(out) = 32970 lb.ft/s
As efficiency is given and output power is known, we can calculate the input power.
ε = P(out) / P(in)
0.65 = 32970 / P(in )
P(in) = 50,723 lb.ft/s
P(in) = 50,723 / 500 hp
= 101.45 hp
the power that must be supplied to the motor is 101.45 hp
Answer:
y = 14238 m. the height of the rocket is much less than this distance therefore the plan will not work.
Explanation:
Let's analyze this exercise, so that the Martian's plan works, the vertical height of the body must be zero when it is more than half of the way to the planet Mars, this is so that Mars attracts it and can arrive.
Let's calculate the maximum height of the launch
at the highest point = 0
y = v_{oy}² / 2g
y = (v₀ sin θ)² / 2g
let's calculate
y = (1250 sin 25)² /2 9.8
y = 14238 m
In the exercise, indicate that the distance to Mars is h = 321770 m, half of this distance is
h / 2 = 160885 m
therefore the height of the rocket is much less than this distance therefore the plan will not work.
The height reached is low, so it is not necessary to take into account the variation of g with height