Question

Use the simulation to answer the following questions. - Open the PhET Projectile Motion Simulation ( https://phet.colorado.edu/en/simulation/projectile-motion) and use it to answer the following questions:

1. For a given launch speed and no air resistance, what launch angle causes the projectile to travel the furthest.   

2. Turn on air resistance. Does air resistance influence the angle you found in part 4? If so, how? (You may need to add quite a bit of air resistance or set the mass fairly low to see an effect)

3. Turn off air resistance. Set the launch angle to 90 degrees (straight up), the mass to 0.1kg and the diameter to .07m. Launch the projectile and use the measuring tape to determine the maximum height that the projectile reaches. (You should assume that the launch height is at the origin of the coordinate system.) Adjust the launch speed until the maximum height the projectile reaches is very close to 20m.

Answer 1

SOlution:

1) The farthest distance is given by the range of the projectile.

Range = Horizontal distance = horizontal velocity x time = v cos * T = ( v cos ) ( 2 v sin ) /g

= ( v^2 sin 2 ) /g

The horizontal distance will be maximum if the angle is 45 degrees because that makes sin 2 = 1

2) If air resistance is switched on the maximum height will decrease. If mass is increased then the maximum height will increase.

3) The aximum height reached is independent of the mass of the object since No air resistance is there.

The maxium height reached Increases as the speed is increased.When the maximum height attained is 20m, launch speed is about 20 m /s