Midterm 1 Study Guide

M. Rocha

Physics 10

Concepts

R = \sqrt{X^2 + Y^2}

Pythagorean Theorem:

\sum{F} = 0

Equilibrium Rule:

\mathrm{Velocity} = \frac{\mathrm{distance}}{\mathrm{time}}

\mathrm{Acceleration} = \frac{\Delta \ v}{\Delta \ t}

a = g = 9.8 \ \frac{m}{s^2} \simeq 10 \ \frac{m}{s^2}

v = a \ t

p = mv

a = \frac{F}{m}

d = \frac{a}{2} \ t^2

Linear Motion:

Free Fall Motion:

Newtons Second Law:

Ft = \Delta(mv)

Momentum and Impulse:

Work and Power:

W = F d

\mathrm{Power} = \frac{W}{t}

\mathrm{Work} = \Delta{\mathrm{E}}

Energy:

\mathrm{PE} = mgh

\mathrm{KE} = \frac{1}{2} m v^2

E = \mathrm{KE} + \mathrm{PE} = \mathrm{C}

Equations

Rotational Equilibrium:

(F \times r)_\mathrm{clockwise} - (F \times r)_\mathrm{counter \ clockwise} = 0

F_{c} = \frac{mv^2}{r}

Centripetal Force:

Gravitational Force:

\mathrm{F_G} = G \frac{m_1m_2}{d^2}

G = 6.67 \times 10^{-11} \mathrm{\frac{N \ m^2}{kg^2}}

Orbits and Satellites:

v_{\mathrm{circ}} = 8 \ \frac{km}{s}

v_{\mathrm{escape}} = 11.2 \ \frac{km}{s}

Rotational Motion:

\omega = \frac{\mathrm{radians}}{t}

v_t = \omega \times r

\mathrm{Torque} = F \times r

\mathrm{Ang. \ Acceleration} = \frac{ F \times r}{I}

\mathrm{Ang. \ Momentum} = I \omega

Practice Problems

1. If you apply 50 N of force upwards and 100 N of force downwards, what is the resultant force?

2. What is the resultant magnitude when adding the two vectors below

23 N

3. What is the average velocity of a runner that finished a 10 km leg of a marathon in 2 hours?

4. A car breaks from 100 km/h to a full stop in 10 s, what is its acceleration?

Practice quiz on canvas

5. A car breaks from 36 km/h to a full stop in 10 s, what is its acceleration? Give your answer in m/s^2

6. What is the height of a cliff if you drop a stone and it hits the ground 5 seconds later

7. Ignoring friction, If an equal force is applied to a 1 kg box and a 2 kg box, the acceleration of the of the 2 kg box is _______ the acceleration of the 1 kg box

8. What is the impulse required to fully stop a 100 g rock moving at 10 m/s? By how much would the force to stop the rock decrease if you take 2 times longer to stop it?

9. Two ice pucks of the same mass collide and stick together after the collision, if one was at rest and the other one had an initial velocity Vi = 4 m/s, what is their velocity after the collision?

10. If you push an elephant on ice skates with a force of 5 N along a distance of 10 m, by how much would the elephant's Kinetic Energy increase (assume there is no friction)? If you pushed the elephant for 10 seconds, what was the power of your push?

11. A 3 kg skate rat drops from the top of a 3 m high half-pipe ramp, what is its Kinetic Energy at the lowest point of the ramp? What about its velocity?