N EWTON ’ S L AWS T EST R EVIEW

I F A MASS FEELS A FORCE, IT ALSO EXPERIENCES AN ACCELERATION. I F THE MASS WERE TO DOUBLE, WHILE KEEPING A CONSTANT FORCE, WHAT HAPPENS TO ACCELERATION ? Doubles Remains the same Reduces to half Depends on the initial size of the mass

A N OBJECT EXPERIENCES A FORCE IN THE POSITIVE X DIRECTION. I F AN EQUAL FORCE ACTS IN THE NEGATIVE X DIRECTION AFTER THE OBJECT HAS TRAVELLED, WHAT HAPPENS ? The forces exactly cancel The forces exactly add You need to use the Pythagorean theorem to get the final answer ?

W HAT HAPPENS TO THE ACCELERATION OF THE OBJECT IN THE PREVIOUS QUESTION ? It immediately decelerates to zero m/s It gradually decelerates to zero It increases rapidly It increases gradually

I F AN OBJECT EXPERIENCES A NET FORCE OF 3 N AFTER BEING PUSHED WITH A FORCE OF 7.5 N, WHAT IS THE FORCE OF FRICTION ? 10.5 N 3 N 7 N 4.5 N

T HE FORCE REQUIRED TO KEEP OBJECTS MOVING WITH A CONSTANT VELOCITY IS : Equal to the force due to gravity Equal to the normal force Equal to 0 Equal to the difference of friction and gravity

I F AN OBJECT IS ON AN INCLINE AND ISN ’ T GIVEN A PUSH, WHAT IS THE FORCE CAUSING IT TO SLIDE DOWN THE RAMP ? ** BE CAREFUL ** Fgx Fgy FN Ffr

I F A 5 KG OBJECT IS ON A 36 º INCLINE, WHAT IS THE FORMULA USED TO CALCULATE F GY ? Fg(sin(36)) Fg(cos(36)) Fn-Fg(cos(36)) Fn-Fg(sin(36))

W HAT IS THE FORCE DUE TO GRAVITY OF THE FOLLOWING MASSES ? A 15 kg object A 15 kg object on a ramp A 15 kg object moving at a constant velocity All forces = -150 N

I F AN OBJECT IS EXPERIENCING 3 FORCES, ONE TO THE LEFT, ONE UP AND ONE DOWN, WHAT CAN WE CONCLUDE ABOUT THE MOTION ? The object has no y motion, only x The object has both x and y motion Nothing The object is staying still

I F AN OBJECT IS TRAVELLING THROUGH THE AIR, AND HAS NO AIR RESISTANCE, WHAT IS THE NET FORCE ON THE OBJECT ? The weight of the object 9.81 N There is none Can’t answer

W HAT IS WEIGHT AND MASS ? Weight is the amount of matter making up an object, mass is the force due to gravity Weight is the force due to gravity, mass is the amount of matter making up an object They are the same thing Weight and mass are the same when an object is moving

W HAT DOES STATIC FRICTION DO ? Prevents an object from initially moving Keeps an object from speeding up once it is already moving Nothing Directs the object’s motion

H OOKE ’ S LAW IS : The gravitational constant attached to a spring The force a spring exerts on the thing supporting it The force on a spring is equivalent to the stiffness constant of the spring and the stretch of the spring A law governing the oscillations of a spring.

I F I EXERT A FORCE ON AN OBJECT OF 10 N AT 30 º N OF E AND YOU EXERT A FORCE OF 6 N ALONG THE NEGATIVE Y AXIS, WHAT IS THE RESULTANT FORCE ? º S of E º N of E 16 7º S of W 4 N N of W

A SPRING HAS A REST LENGTH OF 3 CM. W HEN A 3 KG MASS IS PLACED ON THE SPRING, THE NEW LENGTH IS 45 CM. W HAT IS THE SPRING CONSTANT ?.71 N/m 1.4 N/m 71 N/m.014 N/m

A CAR WITH A MASS OF 900 KG IS TRAVELLING DOWN A LEVEL ROAD AND ACCELERATES 5 M / S 2 BY THE ENGINE EXERTING A FORCE OF 5400 N TO THE RIGHT. W HAT IS THE FRICTIONAL FORCE ? 900 N 5400 N 4500 N 1000 N

W HAT IS THE COEFFICIENT OF FRICTION IN THE PREVIOUS PROBLEM ?

J OE PULLS A 15 KG BOX ACROSS A LEVEL FLOOR. J OE EXERTS A FORCE OF 100 N, 45 0 ABOVE THE HORIZONTAL. T HE COEFFICIENT OF KINETIC FRICTION BETWEEN THE BOX AND THE FLOOR IS W HAT IS THE ACCELERATION ? 2 m/s^ m/s^2 4.7 m/s^ m/s^2