# Thread: Projectiles

1. ## Projectiles

Here i have question based on projectiles.

A small smooth object slides from rest down a smooth inclined plane inclined at 30° to the horizontal.What is the acceleration down the plane and the time to reach the bottom if the plane is 5m long?

Can you explain the way to calculate the acceleration and the other.

2. ## Re: Projectiles

In the picture, mg is the weight of the object and N is the normal force. You need to find the projections of the weight on the x- and y-axes. The projection on the y-axis is canceled by the normal force, and the projection on the x-axis creates the acceleration, which you can find from the second Newton's law.