The answer is A. Hope this helps. :)
Answer:

Explanation:
As we know that train is initially moving with the speed

now we know that

now the final speed of the train when it crossed the crossing


now we can use kinematics here



Now the time to cross that junction is given as



Answer:
The positive displacement from the midpoint of its motion at the speed equal one half of its maximum speed is 3.56 cm.
Explanation:
Maximum speed is :
v (max) = Aω
Speed v at any displacement y is given by
=
(
-
) ........................................................ i
And,
v =
v (max)
or, 2 × v = Aω .................................................... ii
Eliminating ω from equations i and ii,
=
(
-
)
or,
= (
)
=(
) 
or, y = 3.56 cm.
Answer:
1.95 kg
Explanation:
Momentum is conserved.
m₁ u₁ + m₂ u₂ = m₁ v₁ + m₂ v₂
0 = (74.9) (-0.215) + m (8.25)
m = 1.95
120 acceleration oh yeah i am sure about this