A) d = 150, t=5
B) d = 120, t=5
C) d = 180, t=6
D) d = 90, t=6
Correct Answer: D
Solution :
Given: mass of car \[\,m=\text{ }1000\text{ }kg\]; \[~m=\text{ }30\text{ }m/s;\] \[v=0\text{ }m/s\] Retardation, \[-\text{ }a\text{ }=\text{ }5\text{ }m/{{s}^{2}}\] By equation, \[{{v}^{2}}-\text{ }{{u}^{2}}=\text{ }2as\] \[0-{{\left( 30 \right)}^{2}}=-2\times 5\times d\] \[\therefore d=\frac{900}{10}=90m\] \[\text{and a=}\frac{v-u}{t}\therefore t=\frac{v-u}{a}=\frac{0-30}{-5}=6s\]
You need to login to perform this action.
You will be redirected in
3 sec
