Answer:
From the initial height h
Explanation:
When a material or substance is drop from a height h, it possesses potential energy, immediately it is dropped from that height, the potential energy is gradually converted to kinetic energy, it gets to a point where the potential energy equals the kinetic energy, as the material touches the ground, all potential energy has been converted to kinetic energy already
Answer:


Explanation:
Given:
- width of door,

- height of the door,

- thickness of the door,

- mass of the door,

- torque on the door,

<em>∵Since the thickness of the door is very less as compared to its other dimensions, therefore we treat it as a rectangular sheet.</em>
- For a rectangular sheet we have the mass moment of inertia inertia as:



We have a relation between mass moment of inertia, torque and angular acceleration as:



Answer:R=1607556m
θ=180degrees
Explanation:
d1=74.8m
d2=160.7km=160.7km*1000
d2=160700m
d3=80m
d4=198.1m
Using analytical method :
Rx=-(160700+75*cos(41.8))= -160755.9m
Ry= -(74.8+75sin(41.8))-198.1=73m
Magnitude, R:
R=√Rx+Ry
R=√160755.9^2+20^2=160755.916
R=160756m
Direction,θ:
θ=arctan(Rx/Ry)
θ=arctan(-73/160755.9)
θ=-7.9256*10^-6
Note that θ is in the second quadrant, so add 180
θ=180-7.9256*10^6=180degrees
Answer:
a) The sign of the charge is positive.
b) The magnetic force on the particle is 0.050 newtons.
Explanation:
The magnetic force F on a moving charge with velocity v passing through a magnetic field B is:
(1)
a)
Because it is a cross product, we can find the direction of the force using the right-hand rule, that is too the direction of the movement. We have two possibilities here because the velocity vector and magnetic field are perpendicular: the particle deflects towards east or toward west, which depends on the charge of the particle. Note that if you put your right hand fingers, except thumb, pointing towards north (direction of velocity) and later close them in the direction of the magnetic field, if you maintain your thumb perpendicular to this movement it will point towards east (See figure), so that will be de direction of the force if the charge is positive, but if the charge is negative, the direction will be opposite (towards west). So the charge has to be positive to deflects towards east.
b)
Now by 1:

Answer:
The tension in the string is quadrupled i.e. increased by a factor of 4.
Explanation:
The tension in the string is the centripetal force. This force is given by

m is the mass, v is the velocity and r is the radius.
It follows that
, provided m and r are constant.
When v is doubled, the new force,
, is

Hence, the tension in the string is quadrupled.