Name:_________________

Date:_________________

Class:_________________

Drop it!

Introduction

Sir Isaac Newton did a number of things, including the Universal Law of Gravitation which we have already studied. Newton also developed three Laws of Motion. The first law, which we will work with here, states that an object at rest will stay at rest unless acted upon by an outside force. It further states that an object in motion will stay in motion unless acted upon by an outside force.

According to this law, if you are in a car going 45 Km/h, you are also going 45 Km/h. If the car stops suddenly, you are STILL going 45 Km/h. This is why we really ought to wear seat belt at all times. Without a seat belt, the outside force that will stop your body is the windshield! Ouch!

Materials

• Tennis ball

• Lab sheet

• Pencil

Activity 1

Stand still, throw the ball straight up about 2-3 m. Where does the ball land?

Activity 2

Walk at a steady speed and throw the ball straight up. NOW where does it land?

Activity 3

Walk at a constant speed. This time, toss the ball straight up and break into a run as soon as the ball leaves your hand. NOW where does the ball land?

Activity 4

Walk at a constant speed. This time toss the ball straight up and stop as soon as the ball leaves your hand. NOW where does the ball land?

Activity 5

Walk at a constant speed. As soon as you toss the ball up, make a sharp right turn and keep walking. Where does the ball land now?

Questions and Conclusions

1. If you are flying in a plane at 600 Km/h and you jump straight up, where do you land and why?

2. If you are sitting in a car that is at the red light, and the car speeds up suddenly, what REALLY happens? You feel like you are pushed into the seat…are you really?