The correct answer to the question is C i.e C represents the friction from air resistance.
EXPLANATION:
Before coming into any conclusion, first we have to understand friction.
The friction is the opposing force which acts tangentially between two bodies in contact when there is a relative motion between them.
The air resistance is that frictional force which is provided by the air to the moving body through it. Hence, the friction from air resistance will be directed opposite to the motion of the body.
In the given diagram, the airplane is going horizontally. The force A acts in forward direction while force C acts in backward direction. The forces B and D are acting vertically. There is no motion in vertical direction. Hence, the net force of A and C will cause the airplane to move.
As the plane is moving along the direction of A, the frictional force must act along the direction of C.
Given that,
Angle = 30°
Initial velocity = 15 m/s
We need to calculate the time of flight
Using formula of time of flight
Where, u = initial velocity
g = acceleration due to gravity
Put the value into the formula
We need to calculate the final velocity of the ball
Using equation of motion
Hence, The final velocity of the ball is 29.7 m/s.
D.very small amounts of mass.
The answer is C..........
Answer:
Explanation:
mass of 1 L water = 1 kg .
200⁰F = (200 - 32) x 5 / 9 = 93.33⁰C .
260.928 K = 260.928 - 273 = - 12.072⁰C .
water is at higher temperature .
Let the equilibrium temperature be t .
Heat lost by water = mass x specific heat x fall of temperature
= 1 x 4.2 x 10³ x ( 93.33 - t )
Heat gained by copper
= .25 x .385 x 10³ x ( t + 12.072 )
Heat lost = heat gained
1 x 4.2 x 10³ x ( 93.33 - t ) = .25 x .385 x 10³ x ( t + 12.072 )
93.33 - t = .0229 ( t + 12.072)
93.33 - t = .0229 t + .276
93.054 = 1.0229 t
t = 90.97⁰C .
