Question

1. (mc) a ball is thrown horizontally. one second after it is released it has dropped (a) 5 m (b) 10 m (c) 15 m (d) 20 m (e) 45

Explanation:

Step1: Identify the vertical - motion formula

The vertical - motion of the ball is a free - fall motion. The formula for the vertical displacement $y$ of an object in free - fall is $y = v_{0y}t+\frac{1}{2}gt^{2}$, where $v_{0y}$ is the initial vertical velocity, $t$ is the time, and $g$ is the acceleration due to gravity. Since the ball is thrown horizontally, $v_{0y}=0$.

Step2: Substitute the values

We know that $g = 10m/s^{2}$ (approximate value for acceleration due to gravity near the Earth's surface) and $t = 1s$, and $v_{0y}=0$. Substituting into the formula $y=v_{0y}t+\frac{1}{2}gt^{2}$, we get $y = 0\times t+\frac{1}{2}\times10\times1^{2}$.

Step3: Calculate the result

$y=\frac{1}{2}\times10\times1^{2}=5m$.

Answer:

A. 5 m