Question

24) Acat falls from a third-story WOW above the ground, its speed is a) 98m's b) 8.Om's c) 13m's d) 13 m/s2 e) 1.6x10m's 25) A doctor, in between surgery, drives a golfball at an angle of exactly 10 with respect to the horizontal. The ball first hits the ground 210 m from the tee. The ball must have left the tee with an initial speed of about a) 2.1x10m's b) 78.5 m's c)9.8 m's d) 46 m/s 6)65 m/s. 26) On a flatpime, projectile A is launched at an angle of 55° to the horizontal. Another identical projectile B is launched 60° to the horizontal, at the same initial speed. We can confidently say: a) Projectile A has a greater range the projectile B b) Projectile A has a smaller range than projectile B c) Both projectiles have the same horizontal range because they have the same initial speed. d) Whether A has a greater range or B does, depends on the mass of the projectile. 27) We can say with equal confidence, that at the top of its flight, projectile A has a) a greater speed than projectile B. b) has a smaller speed than projectile B c) the same speed as the projectile B d) comes to a stop just as projectile B does. 20 An astronaut lands on an earth-like planet and drops a small lead ball with a mass of 76.5 g from the top of her paceship. The post of release is 30.5 m above the surface of the planet and the ball takes 25 s to reach the ground. The astronaut's mass on earth is 65 kg. Her w o n the planet is 2) 670 N 1) 990 N c) 1020 N d) 69 N c) 390 N .29 The chal period of the earth is one year. The orbital period of Jupiter, whose orbital radius is 5.2 times larger, is a) 27.0 years b) 2.28 year ) 52 years d) 11.85 years e) 1 year 30) Earth orbital spoed is 30 km's Jupiter's orbital speed, whose orbital radius is 5.2 times larger, is a) 5.77 kms b) 13.16 km's c) 30 km's d) 0.07 km/s 0) 156 km/s JI) Ir a car traveling at 20 m's can just about make a turn of radius 120 meters on rough horizontal surface the minimum radius turn it can make ar 60 m/s is a) 1080 m b ) 960 m c) 480 m d) 2 m e) 240 m Page 6 . Q:

Answer 1

25. Sot, Criven information is o=10° ii) R=2lom DA suppose initial speed is u, then formula for range R = W sinzo or u² = ko sinzo orư = 210x9:81 - (240)x(9.8) = 6023 a sin(2x10 - Sin 20 = or u= 77.6 m/s 7 78 ls Hence the closest answer is option b) 78.5 rys