Answer:
4.24m/s
Explanation:
Potential energy at the top= kinetic energy at the button
But kinetic energy= sum of linear and rotational kinetic energy of the hoop
PE= mgh
KE= 1/2 mv^2
RE= 1/2 I ω^2
Where
m= mass of the hoop
v= linear velocity
g= acceleration due to gravity
h= height
I= moment of inertia
ω= angular velocity of the hoop.
But
I = m r^2 for hoop and ω = v/r
giving
m g h = 1/2 m v^2 + 1/2 (m r^2) (v^2/r^2) = 1/2 m v^2 + 1/2 m v^2 = m v^2
and m's cancel
g h = v^2
Hence
v= √gh
v= √10×1.8
v= 4.24m/s
Answer. 30 minutes
Explanation. If he walks 70 m in one minute how long will it take him to walk 2,100 m. Well, this is a simple division problem (you could also use a ratio box).
2100/70= 30. Hope this helps, let me know if it’s correct so others can use it :)
Good luck.
Answer:
Zero
Explanation:
Two long parallel wires each carry the same current I in the same direction. The magnetic field in wire 1 is given by :

Magnetic force acting in wire 2 due to 1 is given by :


Similarly, force acting in wire 1 is given by :
According to third law of motion, the force acting in wire 1 will be in opposite direction to wire 2 as :

So, the total magnetic field at the point P midway between the wires is in what direction will be zero as the the direction of forces are in opposite direction.
You performed 0 work for the fact that work means the distance of movement made on an object not the amount of force it is exposed to. 0 work because it didn't move
A. lunar phases result from the changing lunar mass. Let me know if this helped.