University:
Eastern Kentucky University
Course:
PHY 101 | Conceptual Physics
Academic year:

2022
Views:

226

Pages:

7
Author:

5prinzg1s

Speed Average speed is the total distance traveled by an object divided by the time taken to travel that distance. Instantaneous speed is an object's speed at a given instant of time. Acceleration Acceleration A l i off an object bj is i the h rate off change h off its i velocity and is a vector quantity. For straight-line motion, average acceleration is the rate of change of speed: change in speed Acceleration = time interval vf − vi a= t Acceleration 3T Types off A Acceleartion l ti Speeding Up Slowing Down Turning Distance, Time and Acceleration Vavg = (V1 + V2) (20mph + 60mph) 2 2 = 40mph d = vavg t 30mph 2hr = 60miles d = ½at ½ 2 ½ 10m/s/s 52 = 125m Newton's Law of Gravity Gm1m2 Gravitational force = F = R2 G = 6.67 x 10-11 N•m/kg2 Newton's Law of Gravity • How can we determine the mass of the earth using an apple? – This illustrates the way scientists can use indirect methods to perform seemingly “impossible tasks” Newton's Law of Gravity • H How can we ddetermine t i the th mass off the th earth using an apple? – This illustrates the way scientists can use indirect methods to perform seemingly “impossible impossible tasks tasks” ⎛ GmM ⎞ = mg Gravitational force on apple pp = F = ⎜ ⎟ 2 R ⎝ ⎠ ⎛ gR 2 ⎞ (9.8m / s 2 )(6.4 ×106 m) 2 24 = = × 6 10 M =⎜ kg g ⎟ −11 2 2 6 67 ×10 N ⋅ m / kkg ⎝ G ⎠ 6.67