Chapter-3Falling Objects and Projectile

Motion

Overview

• Explore how objects move under the influence of gravity close to the surface of the earth.

Outline

• Acceleration due to gravity• Falling object• Projectile motion

Why objects fall to the ground when released?

How to observe the Acceleration Due to Gravity?

Galileo’s Method

How to observe the Acceleration Due to Gravity?

Using a Stroboscope

Q2

Acceleration Due to Gravity

Slope = g = 9.8 m/s2.

When you drop objects of different sizes and weights, do they reach the ground at the same time?

When you drop objects of different sizes and weights, do they reach the ground at the same time?

Falling Object

Velocity and Distance for a falling object

Spread Sheet (Excel)Calculations

t (s) v (m/s) d (m)0 0 01 9.8 4.92 19.6 19.63 29.4 44.14 39.2 78.45 49 122.56 58.8 176.47 68.6 240.18 78.4 313.69 88.2 396.9

10 98 49011 107.8 592.912 117.6 705.613 127.4 828.114 137.2 960.415 147 1102.516 156.8 1254.417 166.6 1416.118 176.4 1587.619 186.2 1768.920 196 1960

Velocity VERSUS Time graph

y = 9.8x

0

50

100

150

200

250

0 5 10 15 20 25

Time (s)

V (m

/s)

Distance VERSUS Time graph

0

500

1000

1500

2000

2500

0 5 10 15 20 25

t (s)

d (m

)

Throwing up a ball

Velocity and Distance

Q16

Velocity VS. Time graph

A Cartoon Coyote Falling off a Cliff

Horizontal and Vertical motions

Q: What determines the time of flight?

Q: What determines the time of flight?

A: Vertical motion

Q23

Target Shooting

Football in the air

Angle for maximum Range

CP1