Question

Find the total impulse acting on a body up to 8 seconds from the $F-t$ graph shown.

• A. $20N$
• B. $26N$
• C. $14N$
• D. $40N$

Answer 1

The correct option is B $26N$

Impulse = Area under the $F-t$ graph.
From the given graph
Total area = Area of the trapezium (from $t=0\text{to}t=4s$) $-$ Area of the triangle (from $t=4s\text{to}t=8s$)
$\therefore \text{Total area}=\frac{1}{2}\times (2+4)\times 10-\frac{1}{2}\times 4\times 2=26N$