Answer:
7.8 m/s
Explanation:
Here object is falling with a gravitational acceleration there for we can take acceleration = 10 m/ s² and its constant through out the motion there for we can use motion equation
V = U + at
V - Final velocity
U - Initial velocity
a - acceleration
t - time
V=U+at
107.8=U + 10×10
= 7.8 m/s
The vector, the x-component and the y-component form a rectangle triangle where the vector is the hypothenuse and the x and y components are the two sides.
Calling

the angle between the vector and the horizontal direction (x), the two sides are related to

by

where vy and vx are the two components on the y- and x-axis. Using vx=10 and vy=3 we find

And so the angle is
The answer is that FRICTION PRODUCES HEAT.
C.There is an invisible magnetic field around the magnet where it exerts magnetic force