Answer:
Explanation:
We shall apply conservation of mechanical energy .
initial kinetic energy = 1/2 m v²
= .5 x m x 12 x 12
= 72 m
This energy will be spent to store potential energy . if h be the height attained
potential energy = mgh , h is vertical height attined by block
= mg l sin20 where l is length up the inclined plane
for conservation of mechanical energy
initial kinetic energy = potential energy
72 m = mg l sin20
l = 72 / g sin20
= 21.5 m
deceleration on inclined plane = g sin20
= 3.35 m /s²
v = u - at
t = v - u / a
= (12 - 0) / 3.35
= 3.58 s
it will take the same time to come back . total time taken to reach original point = 2 x 3.58
= 7.16 s
Answer:
answer will be c: 1.5 seconds :)
The magnitude of the force on the charge by the influence of the magnetic field will be 6.6*10^-3 N
<h3>What is magnetic force?</h3>
Magnetic force, attraction or repulsion that arises between electrically charged particles because of their motion.The magnitude of the magnetic force acting on the charge is given by:

where
The magnitude of the charge 
The velocity of the charge 
The magnitude of the magnetic field 
The angle between the directions of v and B 
By substituting the values we will get:


Hence the magnitude of the force on the charge by the influence of the magnetic field will be 6.6*10^-3 N
To know more about Magnetic force follow
brainly.com/question/14411049
Speed is a description of how fast an object moves; velocity is how fast and in what direction it moves. In physics, velocity is speed in a given direction. When we say a car travels at 60 km/h, we are specifying its speed.