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:
Radio waves have longer wavelength
Explanation:
Radio wave is an electromagnetic frequency that has the ability to travel through long distance. They have frequencies shuttling been the range of 10^4 hz and a frequency of 10^12 hz
Light wave is also called visible light. This is because it is visible to the naked eye, despite it being in the electromagnetic spectrum. It's frequency is usually between 4*10^-7 hz and a frequency of 7*10^-7 hz.
As can be seen from both, the radio waves length are quite far stronger than that of the light waves.
Answer:
226.2 m/sec
Explanation:
We have given 
The plank's constant 
Mass of electron 
Now according to Heisenberg uncertainty principle 
So
It's a measure of the acceleration