Explanation​:
At the top of its trajectory, vertical velocity will be zero, but the horizontal velocity will be constant, therefore velocity will be horizontal.
Acceleration due to gravity is always downward

Explanation​:
A. J is an accepted unit of energy

B. Can be resolved thus: Work=force displacement; in terms of units, J=Nm

C. Can be resolved thus: F=ma; in terms of units, N=kg m s^−2. This is a unit of force not a unit of energy and therefore the correct​ answer.

D. Can be resolved thus: W = Fs = mas; In terms of units, J=Nm=kg ms^−2 =kgm^2s^−2

Explanation​:
In order for the plane to travel from A to $B$, the resultant vector of the sum of the wind vector and the vector of the orientation of the plane must point in the same direction as the vector from A to $B$, as shown in the diagram below. For any of the other choices, the resultant will not be in the direction A to $B$.

Explanation​:
Impulse = change in momentum = $Ft$

So the magnitude of the change in momentum = (5.1×10^3)(3.0) = 15300 $Ns$

All responses match this quantity but the number of significant figures needs to be considered. As both of the values used in the calculation have two significant figures, there should be two significant figures in the answer.

In the answer $15000Ns$, the number of significant figures is unclear. It could be 2, 3, 4 or 5. The response $15kNs$ clearly has two significant figures, so it is the best answer.

Explanation‾Explanation​:
Displacement is the area under the graph of velocity-time. Breaking the shape into several areas up to time 7s:

Explanation​:
Horizontal velocity is constant, therefore, the distance travelled will be half in half the time.
Vertical height is proportional to t^2 (s=0.5at^2) therefore in half the time, a quarter of the height will be reached

Explanation​:
The motion of the car here is in the direction of the sum of the two forces vectors from $X$ and $Y$.
The only vector that will add to vector $X$ to produce a net force vector to the right is one in the direction of C.

Explanation​:

Energy transferred to thermal energy will be the work done by the frictional force.

Frictional force = μFN=μmg (where FN=mg)

Work = Fd=μmgd

Explanation​:
The cargo starts with large negative (downward) acceleration. As the cargo container falls, it is speeding up; as it is speeding up, drag force increases, so the acceleration decreases until the cargo container reaches a terminal speed where acceleration is zero. After the parachute is opened, drag force will increase, which is greater than the weight of the cargo container, causing an opposite, upwards, acceleration (deceleration). As the cargo container slows down the drag force decreases, so the net force decreases, and acceleration decreases again until the cargo container reaches a lower terminal speed where acceleration is zero and the forces are balanced.

Explanation​:
I is correct.
The accelerating force is always perpendicular to the direction of motion, therefore no work is done.
$)$, and $\theta$ is always 90$°$.
Also, W=ΔEk and the speed of the object is constant so there is no change in kinetic energy.

II is incorrect.
Because velocity is a vector quantity and the direction is constantly changing, velocity is not constant.

III is correct.
Because velocity is constantly changing, the object is always accelerating.

Explanation​:

There are two forces acting on the pilot which are the gravitational force (weight) and the normal force of the pilot's chair.

The normal force always acts from the chair onto the person. At the top of the loop, this will act vertically downwards.

The weight is always vertically downwards.

Explanation​:
At terminal velocity there is no accleration. Forces must be balanced, therefore the drag force is equal and opposite to the weight.

Explanation​:

Due to the absence of air resistance, the only force acting on the ball is weight and its magnitude is constant. Therefore, the resultant force should be constant during the motion. The only graph that represents this situation is the graph in B.

Explanation​:
The only combination of answers which mentions the correct Newton’s Third Law force pair is C. In Newton’s Third Law force pairs always occur between only the same two objects.

Explanation​:
The change in momentum and impulse applied to the ball are equal, because the impulse is defined as the change in momentum. Increasing one is the same as increasing the other and vice-versa. The slower rebound speed of the second ball causes a decrease in the magnitude of the impulse since the change in momentum is smaller if the final speed $v$ is smaller.

$I=\Delta p=m(v--u)=m(v+u)$

Explanation​:
For any force, the direction is an essential aspect of the quantity. All other options here are scalar quantities.

Explanation​:

The area underneath of the force-time graph gives the change in momentum of the box. Since the area increases with time at a constant rate, the momentum should increase at a constant rate. The only graph that satisfies this condition is the graph in A.

Therefore, the answer is A.

Alternatively, the impulse equation gives Δp=FΔt .

As $F$ is a constant, Δp is directly proportional to $t$ and a straight line through the origin is expected.

Explanation​:

As the direction of motion of the bouncing egg is changed after the collision it has more of a change in velocity than the egg that breaks. Therefore, its momentum changes more.

The time of collision is the same for both situations. According to F=Δp/Δt​, the force acting on the egg that bounces back is greater. By using Newton’s third law, it can be stated that the force acting on the floor from the bouncing egg is greater.