An electric toy car with a mass of 3 kg is powered by a motor with a voltage of 7 V and a current supply of 5 A. How long will it take for the toy car to accelerate from rest to 2 m/s? Physics Electrical Energy and Current Electric Power 1 Answer Narad T. Apr 17, 2017 The time is =0.17s Explanation: Voltage is U=7V Current is I=5A The power is P=UI=7*5=35W Velocity is v=2ms^-1 Mass is m=3kg The kinetic energy is KE=1/2mv^2=1/2*3*(2)^2=6J But, E=P*t The time is t=E/P=(6)/35=0.17s Answer link Related questions What is the SI for a unit of power? What is a kilowatt-hour? Where can I see an electric circuit in my home and car? Why do batteries run down? When an electrochemical cell no longer works, can it be recharged before it can be used again? How does a rechargeable battery work? Question #129ab Why is electric power transmitted at high voltages? What is a unit of electrical current? What is an electric current that reverses its direction in a regular pattern? See all questions in Electric Power Impact of this question 1264 views around the world You can reuse this answer Creative Commons License