PHYSICS EXAM

Using the following mathematical relations that represent two physical quantities:

Quantity (A)= 1 /2 Xmass X velocity squared k.E=1/2mv² Quantity (B)=Force x Displacement. (W = F. d) So that, the dimensional formula (ML² T ^-2 ) represents :

• Quantity (A) only

• Quantity (B) only

• Both (A & B )

• Neither (A) nor (B)

A horse tries to pull a wagon loaded with wood. If the pull force of the horse represents an "action", which force of the following represents the "reaction"?

• A The friction force between the wagon wheels and the ground.

• The pull force of the wagon to the horse.

• The air resistance to the wagon.

• The friction force between the horse legs and the ground

A stone and a ball are projected upwards at the same time, where the stone is projected at 20m/s while the ball at 10m/s. If the maximum height reached by the ball is (H), What is the maximum height reached by the stone? (neglecting air resistance against the movement of stone and ball)

• ½ H

• H

• 2H

• 4H

The figure represents a ball falling freely from a height (H) above the ground. It takes 2s to reach midway to ground ( H). What is the required time for the ball to cover the other half distance to the ground? Given that: (g = 10 m/s² )

• 3 s

• 2 s

• 0.83 s

• 0.5 s

A projectile is projected from a canon by 45^o with the horizontal to reach a maximum height (h) and to cover a horizontal range (X). If the projectile is projected another time by the same canon at the same initial velocity by an angle 60^o . The maximum height and the horizontal range in this case will be:

• more than h , more than X

• more than h , less than X

• less than h , more than X

• less than h , less than X

When two students measured the time taken by a copper sphere to fall freely from a building of 5 m high, they got the two readings below: The first student's reading: (0.1 s) – the second student's reading: (10 s). What do you think about the two readings?

• A The two readings are reasonable.

• The 1 st reading is reasonable while the 2 nd B is not.

• The two readings are not reasonable

• The 2nd reading is reasonable while the 1st D is not

The graph represents the position of two athletes, A and B, who are moving in a straight racetrack in the same direction versus time. At the instant when the athlete(A) is passing by the athlete (B):

• Both displacement and velocity of athlete B are equal to those of A.

• Both displacement and velocity of athlete B are more than those of A

• Both displacement and velocity of athlete B are less than those of A.

• Displacement of athlete B is more than that of A while and the velocity of athlete B equals that of A.

Figure (1) represents the change in position of a moving body (x) which is observed in equal intervals of time, each of 2s, while figure (2) represents (displacement – time) graph of another moving body (y). which statement describe correctly the motion of the two bodies?

• They move at the same velocity.

• Velocity of body (x) is twice that of body (y)

• Velocity of body (x) is half that of body (y)

• Velocity of body (x) is quarter that of body (y)

Using the following relations:

(Force = mass x acceleration)

(Potential Energy = mass x acceleration x height) So, the relation between The Newton (the measuring unit of force)and The Joule( the measuring unit of potential energy) is

• Newton = Joule/meter

• Newton = Joule. Meter

• Newton = meter/ Joule.

• Newton = Joule.

If the length of a rectangle = |5 ± 0.1 | m and

its width = |4 ± 0.2 | m. So, the rectangle area is :

• | 9 ± 0.3 | m²

• |20 ± 0.3| m²

• |20 ± 1.4 | m²

• |20 ± 0.5 | m²