Question

Dynamics question please help i am stuck...!

A model helicopter of mass 5.0 kg rises with constant acceleration from rest to a height of 60 m in 10 seconds. Find the thrust exerted by the rotor blades during the ascent

Answer 1

Thrust required to keep the helicopter stationary
= weight of helicopter
= mg

To find the vertical (upwards) acceleration, we use the formula:
S=ut+(1/2)at²
where
S = distance = 60m
u = initial velocity = 0
t = time = 10 s
a=2(S-ut)/t²
=2(60-0)/10²
=1.2 m s^-2

Total thrust
= 5 kg ( 9.8 + 1.2 ) m s^-2
= 55 N

Answer 2

get a square root of spooky SAS 2 divided by the matrix of two plus two minus X multiply the eigen value of .23 electron volts equals macanca.