Answer:

Explanation:
Velocity of the ship is given as

the direction of the velocity of the ship is making an angle of 11 degree with the current
so we will have two components of the velocity
1) along the direction of the current
2) perpendicular to the direction of the current
so here we know that the component of the ship velocity along the direction of the current is given as



Answer:
88.2 C
Explanation:
The current can be defined as the rate of flow of charge in a conductor.
The relation between charge current and time is given as
I = Q/T
I = current, Q= charge and T = time
that is ampere = coulomb / second
The amount of charge passed is from the negative to the positive terminal
shall be given by:
Q = I * t = 3.5mA * 7h * 3600s/h = 88.2 C
Note: take care of the units.
Answer:
Work done gets doubled.
Explanation:
The work done by a force is given by :
W = Fd
Where
F is force and d is distance move
If the force is doubled and the distance moved remain the same, it would mean that the work done becomes double of the initial work done.
The work done will be equal to the potential energy of the piano at the final position
P.E=m.g.h
.consider the plank the hypotenuse of the right triangle formed with the ground
.let x be the angle with the ground=31.6°
.h be the side opposite to the angle x (h is the final height of the piano)
.let L be the length of the plank
sinx=opposite side / hypotenuse
= h/L
then h=L.sinx=3.49×sin31.6°=0.638m
weight w=m.g
m=w/g=3858/10=385.8kg
Consider Gravity g=10m/s2
then P.E.=m.g.h=385.8kg×10×0.638=2461.404J
then Work W=P.E.=2451.404J