Answer:
10.5min
Explanation:
Given parameters:
Distance = 4200m
Speed = 400m/min
Unknown:
Time taken for this run = ?
Solution:
Speed is the distance divided by the time taken.
Speed = 
Time = 
Now insert the parameters and solve;
Time = 
= 10.5min
Explanation:
- We know that Newton's second law of motion gives the measure of external force acting on an object. It says that the rate of change of linear momentum of an object is directly proportional to the external applied force. It is given by :
Since, p = mv m is mass and v is velocity.
So, if one knows only the constant resultant force acting on an object and the time during which this force acts, one can determine the change in momentum of the impulse.
Answer:
the branch of mechanics concerned with the motion of objects without reference to the forces which cause the motion.
It’s C) because we know that velocity is a vector quantity with direction and speed is only quantity. For example, velocity could be 5 m/s to the east but speed would only be 5 m/s
