Vectors Review

1) Which of the following projectiles would reach the highest height?

• 25 m/s @ 40°• 29 m/s @ 30°• 40 m/s @ 25°

• 40 m/s @ 25°– Highest Vyi

2) A bomber plane is going to drop a bomb on a city, when should the plane release the bomb?

• A) before it reaches the city• B) when it is directly above the city• C) after it passes the city

• A) before it reaches the city

• Bomb maintains horizontal speed of the plane after it is dropped

3) Considering the same bomber plane, where will the plane be relative to the bomb when it hits the ground?

• In front of it• Directly above it• Behind it

• Directly above it, the plane will be directly above the bomb the entire time because both will have the same horizontal velocity

4) A projectile is fired at an angle of 37°, what other angle could the projectile be fired at (with the same speed) so that it

achieved the same range?

• 53° …. Complementary angles produce equal ranges

5) What angle should a projectile be fired at to achieve maximum range?

• 45°

6) What angle should a projectile be fired to achieve maximum height?

• 90° Straight up

7) If you are aiming a rifle at a far away target, where should you aim?

• A) Above the target• B) Right at the target• C) Below the target

• Above the target…. Allowing the bullet to fall due to gravity

8) Which of the following would achieve the greatest range (assume landing at same height it was launched from )?

• 19 m/s @ 30°• 25 m/s @ 22°• 27 m/s @ 21°

27 m/s @ 21°

Δx=Vxt need to find both and multiply

9) If while travelling at a constant velocity in a straight line in a car you fire a gun directly upwards, where will the bullet land.

(ignore air resistance)

• A. In the car• B. Ahead of the car• C. Behind the car

• In the car…. Bullet maintains horizontal speed of the car while in flight

10) A projectile is launched at 24 m/s @ 42°, how long will it take to reach its highest point?

• 1.6 seconds

11) A projectile is launched at 42 m/s @25°and lands back at the same height it was shot from.

• What is its vertical velocity at its highest point?• What is its horizontal velocity at its highest

point?• With what vertical velocity does it hit the

ground with?• With what horizontal velocity does it hit the

ground with?• With what total (resultant) velocity does it hit

the ground with?

What is its vertical velocity at its highest point? 0 m/s What is its horizontal velocity at its highest point? 42cos25With what vertical velocity does it hit the ground with? 42sin25With what horizontal velocity does it hit the ground with?42cos25With what total (resultant) velocity does it hit the ground with? 42 m/s

• 12) A projectile is launched horizontally off a 45 m tall cliff with a velocity of 9.0 m/s. How far away from the base of the cliff did it land?

• 27.3 meters

A projectile is fired at an angle of 25 degrees… which is larger, its x-component of velocity, or its y-component of velocity?

• X component

• A bird is flying 20.0 m above the ground at a horizontal speed of 5.0 m/s, if it drops a twig…

– A) how far will the twig have travelled horizontally from its release point to where it hits the ground?

– B) with what velocity (mag & dir) does it hit the ground?

• A) 10.1 m

• B) 20.4 m/s @ 75.8°

• Relative to a stationary observer Car A is travelling 40 mph East and Car B is travelling 50 mph West, what is the speed of Car B relative to Car A?

• 90 mph W

• Relative to a stationary observer Car A is travelling 40 mph West and Car B is travelling 50 mph West, what is the speed of Car B relative to Car A?

• 10 mph West

• Problem 17, 18, 25/26, 57, 60, 72,74, 77, 78, 84, 86, 87

• A projectile rolls off of a horizontal cliff with a velocity of 6.0 m/s, what is the vertical component of its initial velocity?

• 0 m/s

• Vector A has a magnitude of 18m and points in the direction of 20° above the negative x-axis. Vector B has a magnitude of 30 m and points in the direction of 50° above the positive x-axis.

• Draw and determine the mag & dir of A + B and A-B

• Columbus is 160 miles away from the state of Indiana. If you travelled 200 miles away from Columbus at 38° N of W…

• Did you make it into Indiana?

• No, x-component = 157.6 miles < 160 miles