A toy car has an initial acceleration of 2m/s^2 across a horizontal surface after it is released from rest. After the car travels for a time t consisting of only the car an open system or a closed system, and why? a. Open system because the acceleration of the car is not constant.
b. Open system, because an external force is applied to the car that causes it to accelerate.
c. Closed system, because the speed of the car is as expected in the case where an object has uniform acceleration for a timet
d. Closed system because mechanical energy was not removed from the system as a result of a net force

Open system, because an external force is applied to the car that causes it to accelerate.

Explanation:

In this case, the system under study is the toy car. A system may be open or closed.

An open system is acted upon by external forces but a closed system is not acted upon by any external force.

Since an external force acted on the toy car causing it to accelerate, then it is an open system.

two charges are fixed in place on the x-axis as shown. the charge at x = 0 is negative and has magnitude q = 2 μcoulombs (1 μcoulomb = 10-6 coulombs). the charge at x = d, (d = +12 cm), is positive and has magnitude q = 4 μcoulombs. find a point x = xo along the x-axis at which the electric field is zero.