Answer: 
Explanation:
Given
The velocities of the protons are 400 m/s and 450 m/s
Mass of the Proton is 
Since they travel in the opposite direction, therefore, their momentum cancels out each other.
Momentum is the product of mass and velocity

The direction of momentum is in the direction of proton having 450 m/s velocity.
Answer:
they both uses electric volts
Answer:
44 N/m
Explanation:
The extension, e, of the spring = 2.9 m - 1.4 m = 1.5 m
The work needed to stretch a spring by <em>e</em> is given by

where <em>k</em> is spring constant.

Using the appropriate values,

Explanation:
For velocity,
displaacement/time taken
For speed,
diatance travelled/time taken
It should be a metamorphic rock as those rocks are formed due fue to heat and pressure