Question

1. A train at a constant 62.0 km/h moves east for 32.0 min, then in a direction 46.0° east of due north for 29.0 min, and then west for 42.0 min. What are the (a) magnitude and (b) angle (relative to east) of its average velocity during this trip? 2. A cart is propelled over an XX plane with acceleration components ax 5.5 m/s2 and ay = -2.3 m/s. Its initial velocity has components vox = 9.3 m/s and voy = 14.8 m/s. In unit-vector notation, what is the velocity of the cart when it reaches its greatest coordinate? 3. A projectile is fired horizontally from a gun that is 46.0 m above flat ground, emerging from the gun with a speed of 130 m/s. (a)How long does the projectile remain in the air? (b) At what horizontal distance from the firing point does it strike the ground? (c) What is the magnitude of the vertical component of its velocity as it strikes the ground? 4. A projectile's launch speed is 4.70 times its speed at maximum height. Find the launch angle @o. 5. A rifle that shoots bullets at 457 m/s is to be aimed at a target 49.6 m away. If the center of the target is level with the rifle, how high above the target must the rifle barrel be pointed so that the bullet hits dead center? 6. A ball is shot from the ground into the air. At a height of 7.1 m, its velocity v = 7.51 + 6.0 m/s with horizontal and upward. (a) To what maximum height does the ball rise? (b) What total horizontal distance does the ball travel? What are the (c)magnitude and (d) angle (below the horizontal; give as negative) of the ball's velocity just before it hits the ground? 7. A boy whirls a stone in a horizontal circle of radius 1.5 m and at height 2.4 m above level ground. The string breaks, and the stone flies off horizontally and strikes the ground after traveling a horizontal distance of 9.1 m. What is the magnitude of the centripetal acceleration of the stone while in circular motion? 8. A cameraman on a pickup truck is traveling westward at 16 km/h while he videotapes a cheetah that is moving westward 34 km/hfaster than the truck. Suddenly, the cheetah stops, turns, and then run at 44 km/h eastward, as measured by a suddenly nervous crew member who stands alongside the cheetah's path. The change in the animal's velocity takes 1.7 S. What are the (a) magnitude and (b) direction of the animal's acceleration according to the cameraman and the (c) magnitude and (d) direction according to the nervous crew member?

Answer 1

1) Ansi (a) consider the east direction to be n-axis y-axis North direction to be since the train starts moves to the right along with x-ais. Then the train! changes direction and mores east due to 46 north, clockwise : New from the direction will be 46° north direction directions and cabi 90°- 4 60 = 44" (counter clochwire .b from the east ) 32.0 min - 50 x 32 hr = 0.53 hr S 29. min = 0.48 hr 42 min = 0.70hr

The displacement along urxis an = 62 x 0.53 tl 62x.0.48 * cos 44" +-62 x 0.70 km I du = 10.87 km The displacement along y axis dy = 62 x 0.48 x Bin 44 . km od dy = 20.67 m Resultant displacement de 10.84 t P ? I + sly? dh = (10.84) + (20.67) 2335h a total = Total time = (0.53 + 0.48 +0.70) hr - 1.7.1 ha db 23.35 7 kmland Ang relocity = - Instal – 23.35 kmilan Stotal - 1.t total v= 13.65 kmlhor

tanda de = l | 20.6 + 10 87 62.240
hope this will help you.