To run the physics cart, the fan speed of the cart is manipulated. This is the variable. The cart accelerates due to the speed o
f the fan. Acceleration is therefore the variable. A “constant” is a parameter that stays the same regardless of the variables. One parameter of the cart that is held constant is the .
When the fan of the cart rotates with an increased velocity the force on the cart increases which causes the cart to accelerate. Force and acceleration are variables in this case. Force on the cart is given by the equation
Where m is the mass of the cart and a is acceleration.
In this example, the force is exerted on the cart due to the rotation of the fan. Acceleration is produced due to this force. Thus acceleration is proportional to force.
<span>Charge of the glass bead Q = 8.0 x 10^-9 C
Distance d = 2.0 cm = 0.02 m
Coulombs constant K = 8.99 x 10^9 Nm^2/C^2
Electric Field E = k x Q / d^2 = 8.99 x 10^9 x 8.0 x 10^-9 / (0.02)^2
E = 71.92 / 0.0004 = 17.98 x 10^4
The electric field is 1.8 x 10^5 N/C</span>
