Question
Quantitative Aptitude Question on Time Speed and Distance
If a boy can throw a cricket ball 100 m, then the time required for the ball to touch the ground is
100 meters
200 meters
300 meters
400 meters
100 meters
Solution
To calculate the time it takes for a cricket ball to touch the ground when thrown horizontally, you can use the following formula:
d=21⋅g⋅t2
Where:
● d is the distance the ball travels vertically (in meters).
● g is the acceleration due to gravity (approximately \frac{9.81m}{s^2}$$)
● t is the time (in seconds).
In this case, d is the vertical distance the ball falls from the height it was thrown, which we'll assume is negligible compared to the horizontal distance (100 m).
So, d=0.1m (assuming a negligible height).
Now, we can solve for t:
0.1=21⋅9.81⋅t2
First, multiply both sides by 2 to isolate t2:
0.2 = 9.81 ⋅ t2
Next, divide both sides by 9.81:
t2=9.810.2
Now, take the square root of both sides to find t:
t=(9.810.2)≈0.14 Seconds
So, it takes approximately 0.14 seconds for the cricket ball to touch the ground when thrown horizontally for a distance of 100 meters.
So, the correct option is (A) 100 meters.