Day 2 September 9, 2008

Hello everyone, this is benofschool. We started off class with 5 minutes of finishing off last night's homework and went on to correcting them.
For the first question on the homework the answers are:

Maximum: 101.5 km/h
Minimum: 98.5 km/h

To get the answers we just add the velocities together. The plane is always moving in the north direction so it's velocity (100 km/h) is always positive. The person inside the plane walking the length of it has a varying velocity depending on his/her direction. If the person was walking toward the front of the plane, his velocity in reference (in the point of view of) the ground would be the maximum speed because we have to take into account the velocity of the plane. If the person was walking towards the back of the plane (southward) his velocity would be negative. So his minimum velocity would be less than the plane's velocity because he is moving in the opposite direction of the plane's movement.

The second question involves 2 cars, Car A and Car B, with velocities of 80 km/h and 45 km/h respectively. The first part of this question asks for car B's velocity in reference to Car A if Car A was behind. This is just a simple matter of subtracting Car A's velocity from Car B's giving us a negative result. This is because Car A's velocity is greater than Car B's so then Car A is catching up to it. The answer should be -35km/h for a) and 35km/h for b). The second part involves the 2 cars moving towards each other. Their velocity in reference to any one of them would be the sum of both of the velocities because each of them are moving at their own velocity but we have to take into account the velocity of the other car. The answers for c) and d) should be 125 km/h.

The third homework question was to find the velocity and direction that a boat must travel in order to reach the eastern shore. The direction can be determined by basic Trigonometric skills (SOHCAHTOA) while the velocity can be determined using Ol' Pythagorean's Theorem
(a² + b² = c²). The answer should be 28 km/h [20° S of E].

After that we also recieved another worksheet on Relative Velocities.
The answers for the first three questions on the worksheet are:
1. 6.0m/s
2. 0.73m/s
3. 2.0m/s against the boat

That's is all the things we did today. So homework is the rest of the questions on the new worksheet. MAKE SURE YOU SIGN UP FOR THE BLOG OR YOU WON'T GET THOSE SUPER EASY MARKS!!!!

The next scribe will be Rence

This is your local cuddle monster logging off.
=)