Question

A ball kept on a wall is pushed horizontally with
certain velocity and allowed to move under gravity. Such a
motion is two-dimensional motion with ball covering
displacements in both x and y-directions. But both the x & y
direction motions are independent of each other. Hence,
motion in x-direction can be considered as similar to straight
line motion with no acceleration. Motion in y-direction can be
considered as free fall under gravity.
In the figure shown, ball is pushed horizontally from a
height of 19.6 m, with initial velocity as 10 m/s
[Take g = 9.8 m/s2]


10. The horizontal displacement of projectile after 1 sec.

Answer 1

A ball kept on a wall is pushed horizontally with certain velocity and allowed to move under gravity. Such a motion is two-dimensional motion with ball covering displacements in both x and y directions. But both the x & y direction motions are independent of each other. Hence,

motion in x-direction can be considered as similar to straight line motion with no acceleration. Motion in y-direction can be considered as free fall under gravity. In the figure shown, ball is pushed horizontally from a height of $19.6\mathrm{m}$ , with initial velocity as $10\mathrm{m/s}$

[Take $g = 9.8 \, \text{m/s}^2$ ]

10. The horizontal displacement of projectile after 1 sec.

Solution:

Equation of motion of the ball along the X-axis:

$$S = V _ {x} t + \frac {g _ {x} t ^ {2}}{2},$$

$g_{x}$ - the projection of the gravitational acceleration on the X axis

$$g _ {x} = 0, V _ {x} = V = 1 0 \frac {m}{s}, \Rightarrow$$ $$S = V t = 1 0 \frac {m}{s} \cdot 1 s = 1 0 m$$

Answer: The horizontal displacement of projectile after 1 sec is $10\mathrm{m}$