Explanation:
It is given that,
Total mass is 70 kg
The truck exerts a constant force of 20 N.
Then the net force is given by :
F = ma
a is acceleration of rider

Initial velocity of rider is 0. So, using equation of kinematics to find the final velocity as :

Since, 1 m/s = 2.23 mph
4.28 m/s = 9.57 mph
So, the speed of the rider is 4.28 m/s or 9.57 mph.
Answer:
Gamma radiation or Cathode rays
Explanation:
by striking incident gamma or cathode rays onto the solid when placed on a photographic plate
The <em>mass</em> of an object is a measure of how much stuff it's made of. So it's
a property of the object, like the object's length or color. It doesn't depend on
where the object is located right now, or on what else is around it..
The <em>weight</em> of an object is the measure of the gravitational force between it
and something else. The strength of the force depends on the size of both
masses, and also on how far apart they are. So the weight does depend on
where the object is located right now, and on what else is around it.
I think that sums it up fairly well.
Answer:
<h3>Motion which repeats itself after regular intervals of time is known as periodic motion.</h3>