Prediction Questions : The predictions provided on each lab handout are to help
ID: 250629 • Letter: P
Question
Prediction Questions: The predictions provided on each lab handout are to help you prepare for the lab session. The questions will typically ask you to either do a calculation or think about a concept that will be used in the lab.
Objective: The objective of this laboratory is to understand the relationship between position, velocity and acceleration (specifically for the case of constant acceleration) for moving objects.
Predictions: Answer the following prediction questions and turn them in at the beginning of lab. Each individual is responsible to turn in their own set of predictions (no group predictions please).
1.Predict what the position, velocity and acceleration graphs will look like for a cart rolling UP an inclined ramp. The cart will roll up (slowing as it goes), stop, and then roll back down with the motion detector placed at the top of the incline.
2.Predict what the position, velocity and acceleration graphs will look like when a cart is rolled along a horizontal track and slows due to friction (the cart is moving toward the detector).
3.Predict what the position, velocity and acceleration graphs will look like when a cart on a horizontal air track has a hanging mass (mass on a hanger connected to the cart with a string over a pulley) which causes the cart to accelerate (the cart moves first toward the detector and then away from the detector).
Explanation / Answer
1)
The position graph if we consider moving towards detector is positive... then on Y axis it increases and then decreases.
the velocity will decrease at a constant rate and then become zero and then again increase.. the slope of which is g*sin(angle of incline)
the acceleration is only due to gravity and so it is constant
2)
the position graph if we consider moving towards detector is positive then on Y axis it increases and halts
the velocity will decrease at a constant rate and then become zero
the acceleration (deceleration is constant and equal to frictional force / mass)
3)
The constant force of hanging mass i.e mg is only acting.so the acceleration will be constant and equal to mg/ Mcart and the velocity will go on increase with slope equal to mg/Mcart