Question

$$ s = \frac { 1 } { 2 } ( u + v ) t $$
where ( s ) is the distance traveled by an object (in meters) with an initial velocity ( u )
find ( s ) when ( u ) is ( 8 mathrm { m } / mathrm { s } ), ( v ) is ( 12 mathrm { m } / mathrm { s } ), and ( t ) is 5 seconds.
a. ( 156 mathrm { m } )
b. ( 78 mathrm { m } )
c. ( 100 mathrm { m } )
d. ( 50 mathrm { m } )
reset selection

Explanation:

Step1: Substitute the values into the formula

Given \(u = 8\) m/s, \(v = 12\) m/s, \(t=5\) s. Substitute into \(s=\frac{1}{2}(u + v)t\).

$$s=\frac{1}{2}(8 + 12)\times5$$

Step2: Simplify the expression inside the parentheses

First, calculate \(8 + 12=20\). Then the formula becomes \(s=\frac{1}{2}\times20\times5\).

Step3: Calculate the result

\(\frac{1}{2}\times20 = 10\), and \(10\times5=50\).

Answer:

D. 50 m