Quiz 1

describe the motion of the object

• object is moving at a constant velocity

• The velocity of the object increase linearly with time

• gradient of graph represent velocity of object

• acceleration of the object is zero

choose the correct statements that described the above graph

• object is stationary from 2-7 s

• Total displacement of the object is zero

• The acceleration of the object is zero through out the motion

• The velocity of the object from 7-8 s is negative

 $v=u+at$  

The Equation above is

• derived from the area under the graph v-t

• derived from the gradient of graph v-t

• derived from the area under graph v-t

The acceleration of an object in free fall is

• $9.81\ m\ s^{-2}$

• $-9.81\ m\ s^{-2}$

• $9.81\ m\ s^{-1}$

The velocity of an object at the highest point is

• maximum velocity

• zero

• $9.81\ m\ s^{-2}$

A ball takes 10 s to reach the ground when the ball is dropped from rest, what is the height of the building ?

• 10 m

• 490.5 m

• 981 m

• 100 m

which of the following statement is correct about free falling bodies

• The only force acting on the object is the Gravitational force

• when an object is tossed upward the velocity of the ball decreases by -9.81 m s−1

• when an object is dropped, its velocity increases by 9.81 m s−1

• $s_y$ of the object tells you the displacement of the rom the initial point, if initial point is taken as the origin

in projectile, launched at an agle  $\theta$  , how the final elocity of the projectile compare to the initial velocity when  it lands on the same horizontal level

• same magnitude and direction

• same magnitude but opposite in diretion

• velocity final is bigger due to the gravitational acceleration

• it has zero final velocity

which of the following statements are correct about the motion above

• The horizontal velocity of the projectile is constant

• Horizontal displacment and range of the projectile can be calculated using the equation

• The vertical velocity of the projectile decreases as the projectile climbs up to the maximum height

• The direction of the velocity is always chaging with time

the graph show the change in the altitude of a sky divers before and after he open his parachute, which of the following statements accurately describe the motion of the diver.

• before : The velocity increases as the altitude decreases

  after : moving a lower constant velocity

• before : the velocity decreased rapidly

  after : The velocity becomes constant

• before : The velocity increases as the altitude decreases

  after : the velocity goes to zero