A boy throws a ball and accidentally breaks a window. The momentum of the ball and all the pieces of glass taken together after the collision is the same as <span>the momentum of the ball before the collision. I think you forgot to give the choices along with the question. I hope that the answer has come to your great help.</span>
Answer:
time required after impact for a puck is 2.18 seconds
Explanation:
given data
mass = 30 g = 0.03 kg
diameter = 100 mm = 0.1 m
thick = 0.1 mm = 1 ×
m
dynamic viscosity = 1.75 ×
Ns/m²
air temperature = 15°C
to find out
time required after impact for a puck to lose 10%
solution
we know velocity varies here 0 to v
we consider here initial velocity = v
so final velocity = 0.9v
so change in velocity is du = v
and clearance dy = h
and shear stress acting on surface is here express as
= µ 
so
= µ 
............1
put here value
= 1.75× × 
= 0.175 v
and
area between air and puck is given by
Area = 
area = 
area = 7.85 × 
m²
so
force on puck is express as
Force = × area
force = 0.175 v × 7.85 × 
force = 1.374 × v
and now apply newton second law
force = mass × acceleration
- force = 
- 1.374 × v = 
t = 
time = 2.18
so time required after impact for a puck is 2.18 seconds
When the experiment is replicated, this means the conduction of the second experiment, should be related, or similar, to your first results.
Nothing can travel faster than the speed of light. As such, perceptions of objects and time change as they approach light speed, but the laws of physics remain consistent regardless of speed. Objects will appear shortened and time will appear to slow down around an observer approaching near light speeds, but all quantities still exist as they did before and all causality is preserved, even if observers in different points or traveling at different speeds will report different things.
Answer:
B on edge
Explanation:
the piles of the magnetic field generated around the armature are attracted to the opposite poles of the permanent magnent. As the opposite poles align, the commutator reverses the current direction so like poles are aligned and the armature continues to spin
