1 / 19

What is the resultant of a pair of forces 100N upward and 75N downwards? 25N up

What is the resultant of a pair of forces 100N upward and 75N downwards? 25N up. Why is speed scalar and velocity vector? Speed is only a number. Velocity is speed in a given direction. What is the end point for: 45° for 3 blocks, S for 7. Calculate the resultant for the following:

Download Presentation

What is the resultant of a pair of forces 100N upward and 75N downwards? 25N up

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. What is the resultant of a pair of forces 100N upward and 75N downwards? 25N up

  2. Why is speed scalar and velocity vector? Speed is only a number. Velocity is speed in a given direction.

  3. What is the end point for: 45° for 3 blocks, S for 7

  4. Calculate the resultant for the following: 8m east, 2m north, 6 m west 22+22 = √8 = 2.9m NE

  5. A ball is dropped from a 60m high building. How far will it have fallen after 3.0 seconds? y = ½ gt2 4.8m/s2 x 9s2 = 44.1m

  6. In the absence of air resistance, why does the horizontal component of velocity for a projectile remain constant? No other forces are involved.

  7. Why does motion in the vertical component change? Gravity

  8. A bird flies at 20km/h. How long does it take to fly 400km? 400km/ 20km/hr = 20hours

  9. A rock is thrown at a target 40m away. It hits the target in 4.0 seconds. What is the speed of the rock? 40m/4.0 seconds = 10m/s

  10. A stone is dropped from a bridge and hits the ground after 4.0 seconds. How high is the cliff? y = ½ gt2 4.8m/s2 x 4.0s2 = 78.4m

  11. A salmon jumps up a waterfall to return home to spawn. The waterfall is 2.0m high. What minimum speed must the fish meet to jump the waterfall? vf2 = vyo2 + 2a ∙ d = 6.26m/s

  12. What is the resultant path of a ship traveling north at 8m/s if the tide is pushing at 2m/s east. What is the angle? 82m/s + 22m/s = √68m2/s2= 8.2m/s 8/2 tan-1 = 76°

  13. A rock is dropped and hits bottom 5 seconds later. What is its velocity just before it hits bottom. vy = vyo + ayt 9.8m/s2 x 5 s = 49m/s What is the height of the cliff? y = ½ gt2 = 4.9m/s2 x 25 s2 = 122.5m

  14. A rock is thrown from a cliff at 20m/s. What is the horizontal velocity after 2.0 seconds? 20m/s What is its vertical velocity in 2.0s? y = ayt 9.8m/s2 x 2.0 s = 19.8m/s

  15. A rock is thrown from a cliff at 20m/s. What is its horizontal displacement after 3.0s? x = vxi t = 20m/s x 3.0s = 60m

  16. A man shoots a gun at 2m above ground. The bullet is fired and hits the ground 1000m away. What vertical velocity did the bullet hit the ground? • vfy2 = voy2 + 2a x d • 2(9.8m/s2) x 2m = vfy2 • √39.2m2/s2 = 6.26m/s

  17. A ball is projected horizontally from a point 245m above the ground. How long does it take to reach the ground? • y = ½ gt2 • t2 = y ÷ ½ g • 245m ÷ 4.9m/s2 = √50s2 • = 7.07 seconds

  18. A ball is projected horizontally from a point 245m above the ground. How long does it take to reach the ground? = 7 seconds (previous slide) • If the ball strikes 49m horizontally from the point of projection, what is the horizontal velocity? • v = d/t 49m/7s = 7m/s

  19. A projectile is shot upward at a 60° angle from the ground at 60m/s. What is the vertical component of velocity? • y = 60m/s (sin 60°) = 52m/s • What is its horizontal component of velocity? • vx= v (cosӨ) • vx = 60m/s (cos 60°) = 30m/s • How far in the x direction has it gone in 3 seconds? • x = vt 30m/s x 3 seconds = 90m

More Related