Exam 1

Question 1

Vectors M and N obey the equation M+N=0 These vectors satisfy what

Answer 1

Vectors M and N have the same magnitude

Question 2

If a vectors components are all negative, then the mag of the vectors is negative T/F

Answer 2

False, Magnitude cant be negative

Question 3

An object moves in a cir Circular path of a constant Speed. Compare the direction of the object velocity and acceleration factors

Answer 3

The vectors are perpendicular to each other

Question 4

A ball is thrown horizontally from the top of a tower At the same instant that a stone is dropped vertically. Which object is traveling faster when it hits the level ground below if neither of them Experiences any air resistance?

Answer 4

The ball

Question 5

A boulder rolls off of a very high cliff and experiences no significant Air resistance while it is following its trajectory is never truly vertical true or false

Answer 5

True

Question 6

For general project on motion with no air resistance the horizontal component of a projectile is acceleration

Answer 6

Is always zero

Question 7

A rock is thrown from the upper edge of a tall cliff at some at some angle above the horizontal. It reaches its height point and starts falling down which of the following statements about the rocks motion are true just before it hits the ground

Answer 7

It’s horizontal velocity component is the same as it was just as it was launched

Question 8

In an air free chamber a pebble is thrown horizontally and at the same time a second purple is dropped from the same height compared the time of fall of the two pebbles

Answer 8

They hit the ground at the same time

Question 9

A plus B equals C and their magnitude are given by a plus B equals C in vectors a and B are oriented

Answer 9

Parallel to each other in the same direction

Question 10

James and John dive from an overhang into the lake below James simply drops straight down from the edge John takes a running start and jumps with a whole initial horizontal velocity of 25 m/s compared the time it takes each to reach the lake if there is no air resistance

Answer 10

James and John will reach the surface of the lake at the same time

Question 11

The magnitude of a vector can NEVER be less than the mag of any of its components
True or False

Answer 11

True

Question 12

In order to get an object moving, you must push harder on it than it pushes on you T/F

Answer 12

False

Question 13

While flying horizontally in an airplane you noticed that a string dangling from the overhead luggage compartment hangs up 15° away from the vertical towards the front of the plane using this observation you can conclude that the airplane is

Answer 13

Accelerating backwards

Question 14

The acceleration due to gravity is lower on the moon then on the earth which one of the following statements is true about the mass and weight of an astronaut on the moon surface compared to earth

Answer 14

Mass is the same weight as less

Question 15

If the rockets of a spaceship an outer space suddenly lose power and go off the spaceship will gradually slow to a stop (away from gravity) T/F

Answer 15

False, will go forever in absence of gravity

Question 16

A 20 ton truck collides with a 1500 pound car which of the following statements must be true

Answer 16

During the collision, the force on the truck is equal to the force on the car

Question 17

You pull on a crate with a rope if the crate move the ropes pull on the crate must have been larger than the great pool on the road but if the crate does not move off of these polls must have been equal T/F

Answer 17

False, Rope doesn’t apply force, person does

Question 18

A bucket is being lowered by a very light rope with constant download velocity the tension in the rope must be

Answer 18

Equal to the weight of the bucket

Question 19

An object is moving with constant nonzero velocity which of the following statements about it must be true

Answer 19

Net force on the object is zero

Question 20

A fireman sliding down a purple as he speaks of potatoes grip on the pole does increasing the vertical friction force that the porch starts on the firemen when the force on his hand equals his weight what happens to the firemen

Answer 20

The fireman continues to descend with constant speed

Question 21

An object of weight W is in freefall close to the surface of the earth the magnitude of the force that the object exerts on earth is

Answer 21

Equal to W

Question 22

An object of mass M rest on a flat table the earth poles on this object with a force of magnitude MG what is the reaction force to this pull

Answer 22

The object pulling a port on the earth with force mg newtons 3rd law equal and opposite reaction

Question 23

In a collision between a huge SUV and a small hybrid car SUV exerts a large force on a hybrid car than a hybrid exerts on the SUV T/F

Answer 23

False, force Same only direction differs

Question 24

If you pound a feather with a hammer which one feels the greater force

Answer 24

The size of the force is equal on both of them