Answer:

Explanation:
The change in potential energy can be expressed as:

where K is a constant with a value of
, q1 and q2 are the charges of the proton and the electron and r is the distance between them.
The charge for the proton is
and the charge for the electron is
.
Converting r=1.0nm to m:

Replacing values:


Part a)
in horizontal direction there is no gravity or no other acceleration
so in horizontal direction the speed of clam will remain same

Part b)
In vertical direction we can use kinematics



part c)
if the speed of crow will be increased then the horizontal speed of the clam will also increase but there is no change in the vertical speed
This is a question that would have literally have taken two seconds to look up on google but the answer is 1.88 years.
Answer:
u = 449 m/s
Explanation:
Given,
Mass of the bullet, m = 26 g
Mass of the wooden block,M = 4.7 Kg
height of the block,h = 0.31 m
initial speed of the block, u = ?
Using conservation of energy




v = 2.47 m/s
Now, using conservation of momentum to calculate the speed of the bullet.
m u + M u' = (M+m)v
m u = (M+m)v
0.026 x u = (4.7+0.026) x 2.47
u = 449 m/s
Hence, the speed of the bullet is equal to 449 m/s.


Now


- Lower mass=Higher acceleration
- Lower Force=Lower Acceleration
Option B has lowest mass and highest force hence its correct