Physics: motion

Question 1

what three formulas describe motion under constant accelaration

Answer 1

Question 2

what is the definition of velocity

Answer 2

velocity is defined as displacement per unit time

Question 3

what formulas would be used to find the velocity of an object fired horizontally with a speed of V_H

Answer 3

Question 4

what formulas would use to find the horizontal and vertical velocity of an object with speed v and shot at an angle theta

Answer 4

Question 5

what formulas would be used to find the time of flight of an object fired horizontally with a speed of V_H

Answer 5

Question 6

what for formulas would be used to calculate the time of flight of an object launched at an angle theta and a speed of v

Answer 6

Question 7

what for formulas would be used to calculate the time of flight of an object launched at a Hight of H an angle theta and a speed of v

Answer 7

Question 8

what formulas would be used to find the vertical displacement of an object fired horizontally with a speed of V_H

Answer 8

Question 9

what for formulas would be used to calculate the vertical displacement of an object launched at an angle theta and a speed of v

Answer 9

Question 10

what effect does changing the Height have on range when angle is kept constant

Answer 10

it increase the range as t increase because of “sub in formula” and therefore Vh increase because s=v*t

Question 11

what effect does changing the launch angle have when H is kept constant

Answer 11

By decreasing the launch angle the Vh is increased. T is decreased by the increase in Vh is larger so Sh increases overall

Question 12

why does a launch angle of 45 degrees optimize range

Answer 12

it is because at 45 degrees both Vh and Vv are equal. this means that the time of flight is optimized for the vertical component

Question 13

what factors effect drag force and why

Answer 13

Speed- the faster an object moves the more particles it collides with. drag force increase by square fo is speed doubles drag quadruples.
Cross-sectional area- cross sectional area is directly proportional to drag. and the larger something is the more particles it hits.
density of the medium- the denser the medium is the more particles there are therefore the more particles the object will collide with.
shape- an object with a stream line body allow particles of flow over an around them decreasing there drag coefficient.

Question 14

what is the unit for momentum

Answer 14

sN or kg m s−1

Question 15

what is the law of conservation of momentum

Answer 15

the Law of conservation of momentum states that in an isolated system there there are no external forces. the total momentum before an interaction will e equal to the total momentum after an interaction

Question 16

what is centripetal accelaration

Answer 16

the accelaration experienced by an object undergoing uniform circular motion always act perpendicular to the objects velocity and towards the center of the circular path.

Question 17

what is uniform circular motion

Answer 17

uniform circular motion is when an object travels at a constant speed in a circular path

Question 18

what is the formula used to find minimum banking angle

Answer 18

Question 19

what units are used to measure gravitational field strength

Answer 19

Nkg-1 or ms^-2

Question 20

what is Kepler’s first law of planetary motion

Answer 20

all planets move in elliptical orbits with the sun at one focus

Question 21

what is Kepler’s second law of planetary motion

Answer 21

a line drawn from the center of the sun to the center of the planet sweeps the same area over equal time intervals

Question 22

what is Kepler’s third law of planetary motion

Answer 22

the period of revolution of a satellite squared is proportional to the radius of the orbit cubed

Question 23

what is Newtons first law

Answer 23

An object at rest remains at rest, and an object in motion remains in motion at constant speed and in a straight line unless acted on by an unbalanced force.

Question 24

what is Newtons second law

Answer 24

the greater the mass of an object, the more force it will take to accelerate the object

Question 25

what is Newtons third law

Answer 25

Whenever one object exerts a force on another object, the second object exerts an equal and opposite on the first.

Question 26

what is an inertial frame of reference

Answer 26

an inertial frame of reference is one in which newtons laws of motion apply. an inertial frame of reference is therefore either stationary or moving with a constant velocity

Question 27

what are the two postulates of the theory of special relativity

Answer 27

1. the speed of light is an absolute constant. 2. the laws of physics are the same in all inertial frames of reference

Question 28

the concept of simultaneity

Answer 28

two events that are simultaneous in one frame of reference will not be simultaneous in a frame of reference that is moving with respect to the other

Question 29

what is a proper unit

Answer 29

a proper unit is when something is measured in a reference frame of which such thing being measured is at rest

Question 30

what is time dilation

Answer 30

time dilation is the slowing down of clocks that are in motion relative to the observer

Question 31

what is length contraction

Answer 31

length contraction is the decrease if length of an object in motion relative to an observer

Question 32

what is relativistic mass

Answer 32

relativistic mass is when the mass of an object increases relative to a stationary observer

Question 33

what is coulombs law

Answer 33

the electric forces of attraction or repulsion are directly proportional to the product of the two charges and inversely proportional to the square of the distance between centers