Forces 11/6/14

Homework and Free Response All HW problems use Newton’s 2nd Law or force vector addition EX) #2 on p. 98 A net force of 265 N accelerates a bike and rider at 2.30 m/s2. What is the mass of the bike and rider?

Net Force Non-Zero Net Force: The object is accelerating No Net Force: The object is at rest or has a constant velocity

Pulleys Pulleys change the direction of the force not the magnitude

A 225 g mass hangs from a pulley what is the tension in the string?

Force Table Challenge Activity Everyone needs to turn in the own calculations

Force Table Challenge Activity 11/6/14 & 11/7/14

Today’s Challenge - Objective You will be able to calculate 2 tension forces and you have to determine the magnitude and direction of a 3rd so the net force of the table system is zero (at rest).

The Challenge (#1) There are 2 masses hanging creating tension in the string 1. Calculate the tension in the two stings 2. Draw a force diagram FBD the force table 3. Use this FBD to calculate the third force vector needed to balance the 3 vectors so that the circle stays in the very middle of the center post. You need to show your work for this calculation very clearly. 4. Using your calculation for the third force vector you will apply the appropriate masses at the angle that you calculated to balance the 3 force vectors as exactly as possible.

The Next Challenges #1) 50 g at 225° and 100 g at 0.0° #2) Move the 50 g mass from 225° to 250° and repeat the process from Challenge #1 #3) Keep the 50 g mass at 250° and move the 100 g mass to 330° and repeat the process from Challenge #1 #4) Move the 50 g mass to 210° and move the 100 g mass to 340° and repeat the process from Challenge #1