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mental ability

3. What’s the next number in the sequence: 2, 4, 8, 16?
A) 32
B) 36
C) 40

Motion in a straight line

A ball is dropped from a height of 90 m on a floor. At each collision with the floor,
the ball loses one tenth of its speed. Plot the speed-time graph of its motion
between t = 0 to 12 s.

mental ability

2. A car travels 250 miles in 5 hours. What’s its average speed?
A) 45 mph
B) 50 mph
C) 55 mph

mental ability

1. A bakery sells 250 loaves at $2 each. If they increase price by 10%, how much more revenue?
A) $25
B) $50
C) $62.50

Motion in a straight line

Read each statement below carefully and state with reasons and examples, if it is
true or false ;
A particle in one-dimensional motion
(a) with zero speed at an instant may have non-zero acceleration at that instant
(b) with zero speed may have non-zero velocity,
(c) with constant speed must have zero acceleration,
(d) with positive value of acceleration must be speeding up.

mental ability

5. Five houses, each painted a different color (blue, green, red, white, yellow), are occupied by five people (John, Mike, Emma, Sarah, Tom) of different nationalities. Which color is John’s house?
( Assume: Emma lives in the yellow house, Mike lives next to the green house)

A) Blue
B) Red
C) White

Motion in a straight line

A player throws a ball upwards with an initial speed of 29.4 m s–1
.
(a) What is the direction of acceleration during the upward motion of the ball ?
(b) What are the velocity and acceleration of the ball at the highest point of its motion ?
(c) Choose the x = 0 m and t = 0 s to be the location and time of the ball at its
highest point, vertically downward direction to be the positive direction of
x-axis, and give the signs of position, velocity and acceleration of the ball
during its upward, and downward motion.
(d) To what height does the ball rise and after how long does the ball return to the
player’s hands ? (Take g = 9.8 m s–2 and neglect air resistance).

mental ability

4. A bat and ball cost $1.10. The bat costs $1.00 more than the ball. How much does the ball cost?
A) $0.05
B) $0.10
C) $0.15

mental ability

3. You have 8 balls, one of which is slightly heavier. How can you find the heavier ball in 2 weighings?
A) Divide and weigh
B) Weigh 3-3-2
C) Weigh 4-4

mental ability

2. A snail is at the bottom of a 20-foot well. Each day, it climbs 3 feet, but slips 2 feet. How many days to reach the top?
A) 18
B) 20
C) 22