1. Tardigrade
  2. Question
  3. Physics
  4. A toy car with charge q moves on a frictionless horizontal plane surface under the influence of a uniform electric field E . Due to the force q vecE , its velocity increases from 0 to 6 m/s-1 in one second duration. At that instant the direction of the field is reversed. The car continues to move for two more seconds under the influence of this field. The average velocity and the average speed of the toy car between 0 to 3 seconds are respectively

Question Error Report

Thank you for reporting, we will resolve it shortly

Back to Question

Q. A toy car with charge $q$ moves on a frictionless horizontal plane surface under the influence of a uniform electric field $E$ . Due to the force $q\,\vec{E}$ , its velocity increases from $0 \,to\, 6 m/s^{-1}$ in one second duration. At that instant the direction of the field is reversed. The car continues to move for two more seconds under the influence of this field. The average velocity and the average speed of the toy car between $0 \,to\, 3$ seconds are respectively

NEETNEET 2018Electric Charges and Fields

Solution:

image
Acceleration a $=\frac{6-0}{1}=6\, ms ^{-2}$
For $t=0$ to $t=1 \,s$
$S_{1}=\frac{1}{2} \times 6(1)^{2}=3\, m \ldots$...(i)
For $t=1 \,s$ to $t=2 \,s$,
$S_{2}=6.1-\frac{1}{2} \times 6(1)^{2}=3 \,m \ldots .$ (ii)
For $t=2\,s$ to $t=3 \,s$
$S_{3}=0-\frac{1}{2} \times 6(1)^{2}=-3 \,m$....(iii)
Total displacement $S=S_{1}+S_{2}+S_{3}=3\, m$
Average velocity $=\frac{3}{3}=1\, ms ^{-1}$
Total distance travelled $=9 \,m$
Average speed $=\frac{9}{3}=3\, m s^{-1}$