A spring scale is attached to a cart and is being pulled with a force of 10.5 N. If the car moves to the right with a constant velocity. What are the magnitude and direction of the frictional force?
If the cart moves with a uniform velocity, it means that the forces are in equilibrium (absence of acceleration).
The only vertical forces acting on the cart are its weight (mg) and the normal reaction on the wheel exerted by the floor. Therefore the normal reaction equals mg.
The only horizontal external forces are the spring scale which registers 10.5N and the frictional force.
Can you take it from here?
i do not know what to do from here. this is where I was stuck. what do I do from here.
There are two horizontal forces, the frictional force F1, and the spring-scale pull (F2), which registers 10.5N.
Since the two are in equilibrium, they have to be equal and opposite. So F1=F2.
What is F1?
To determine the magnitude and direction of the frictional force acting on the cart, we need to consider the fact that the cart is moving at a constant velocity. When an object moves at a constant velocity, it means that the sum of all forces acting on it must be zero.
In this case, the force pulling the cart to the right with a magnitude of 10.5 N is balanced by the frictional force, which acts in the opposite direction. Therefore, the magnitude of the frictional force is also 10.5 N, but in the opposite direction (to the left).
It's important to note that the direction of the frictional force is always opposite to the direction of motion or the applied force when the object is moving at a constant velocity. This frictional force is often referred to as the "kinetic friction" force.