LA 134111 _o_f mass 3 kg has a linear momentum of 12 kg nix's .What is the kinetic energy of the ball? a) 12 J b) 2.4 J c}24 J d) 48 J e) None of these are true git. A (M=N#) kg rock is released from rest at height H=50rn. Detenninm ratio R=KEIPE of the kinetic energy K.E.=Mv2f2 and gravitational energy PE=U=MWWgwgi1 at 13:}th h= 36m: a)0.m;__b) 0.763; c)0.686; d)0.389; e) None of these are true 3. Two massive objects (M1=M2=N#=llgg attract each other with a force F. What haggens the force between them if one mass is doubled, the other mass is tripled, and the separation between their centers is reduced to one-fourth its original value? L M: F=G M; leR2 ) The force is now equal to : ' a)36 F b)24 F c}3Ff8 d)96 F is) None of these are true 4. A rock with mass M={#_I__J___]kg is observed to be falling with acceleration of 8.7 n'n's-1 . What is the magnitude of the force of air resistance? a} 0.2 {#QANSHN} c) 1.2 (#N) d)2.1 {#N} e] None ofthese are true 5. A m=0.3kg mass . attached to the end of a 50.75 m string . is whirled around in circular horizontal path. If the maximum tension that the string can withstand is F=250 N. then what maximum velocity ( in nits) can the mass have if the string is not to break? I-lint: Fans-3h 11]37'52 13130.51 c 122.25 a} 34.98 e) None or' these are me 6. A river flows due east at 18 km/h. A boat crosses the 1820 m wide river by maintaining a constant velocity of 27 mi/h due north relative to the water. If no correction is made for the current, how far downstream does the boat move by the time it reaches the far shore? Hint: Dx=Vx T; Dy=Vy T a) 160m b)275m c)758 m d)960m e) None of these are true 7. How long will it take a motor with power [ P=2 (#N) W] to lift a [ m= 0.25x (#N)kg] piano to 26 m above ? Hint: U=P t ; P=U/t; U=mgh . a) 0.12 s b) 14.1 s c)28.2 s d) 32. 1s e) None of these is true 8.A car with mass M=(#N) kg moving east with speed 18 mi/h collides with horizontal coiled spring (spring constant k=4(#N) kg/s and is brought to rest in a distance of X m. Find X . Hint: Mv- /2 =kX- /2 a) 2m b) 3m c) 4 m d)5m e) None of these is true