- Home
- Standard 9
- Science
7. MOTION
medium
The velocity$-$time graph of a car is given below. The car weighs $1000\, kg$.
$(i)$ What is the distance travelled by the car in the first $2$ seconds ?
$(ii)$ What is the braking force at the end of $5$ seconds to bring the car to a stop within one second ?
Option A
Option B
Option C
Option D
Solution
The distance fravelled by the car in first $2$ seconds $=$ Area of $\Delta ABE$
$=1 / 2 \times AE \times BE$
$=1 / 2 \times 2 \times 15=15 m$
Mass of the car $=1000\, kg$
$F=m \times a,$ where $a=$ slope of the graph $CD$
$a=\frac{0-15}{6-5}=\frac{-15}{1}=-15 m s ^{-2}$
$F =m \times a=1000 \times-15=-15000 N$
Standard 9
Science
