0 attempts
0% avg
UBQ Credits
| Step | Derivation/Formula | Reasoning |
|---|---|---|
| A1 | [katex] T – Mg = \frac{Mv^2}{L} [/katex] | This is the force equilibrium equation at the bottom point. [katex] T [/katex] is the tension in the string, [katex] M [/katex] is the mass of the ball, [katex] g [/katex] is the acceleration due to gravity, [katex] v [/katex] is the velocity of the ball, and [katex] L [/katex] is the length of the string. |
| A2 | [katex] T = 3Mg [/katex] | The tension at the bottom is given to be three times the weight of the ball. |
| A3 | [katex] 3Mg – Mg = \frac{Mv^2}{L} [/katex] | Substituting the tension value into the equilibrium equation. |
| A4 | [katex] v = \sqrt{2gL} [/katex] | Simplifying the equation for [katex] v [/katex], observe [katex] M [/katex] cancels out. This is velocity at any given point around the circle. |
| A5 | [katex] F_{\text{centripetal}} = \frac{Mv^2}{L} [/katex] | At the top, we can use the velocity calculated in the previous step to find the centripetal force required to keep the ball moving in the circle. |
| A6 | [katex] 2mg [/katex] | Substitute in the equation for velocity (from step A4) so that the final equation is in terms of [katex] M \, g \, L [/katex] |
| B1 | [katex] v_{\text{top}} = \sqrt{v^2 – 4gL} [/katex] | Using conservation of energy. [katex] KE_{\text{bottom}} + PE_{\text{bottom}} = KE_{\text{top}} + PE_{\text{top}} [/katex]. The velocity at the top is found by noting the potential energy difference between top and bottom. Simplify by substituting [katex] v [/katex] from A4. |
| B2 | [katex] v_{\text{top}} = \sqrt{2gL – 4gL} [/katex] | [katex] = \sqrt{-2gL} \rightarrow [/katex] which is zero since [katex] 2gL > 4gL [/katex] |
| C1 | [katex] t = \sqrt{\frac{4L}{g}} [/katex] | Ball falls freely under gravity and has no initial vertical velocity, so [katex] \delta y = \frac{1}{2}gt^2 [/katex]; solving for [katex] t [/katex] gives the time to fall a distance [katex] L [/katex]. Note that the displacement from the top to the bottom is twice the radius of the circle or [katex] 2L [/katex]. |
| D1 | [katex] \Delta x = v_0t [/katex] | The horiztontal distance traveled by any projectile is the product of the horiztonal speed and the time in air. |
| D2 | [katex] \sqrt{2gL} \times \sqrt{\frac{4L}{g}} [/katex] | Substitute in velocity from Step A4 and time from step C1 |
| D3 | [katex] \sqrt{8}L [/katex] | Simplify |
(a) The net force on the ball at the top is [katex] 2Mg [/katex], downward.
(b) The velocity of the ball at the top is [katex] v = \sqrt{2gL} [/katex].
(c) The time it takes to reach the ground is [katex] \sqrt{\frac{4L}{g}} [/katex].
(d) The horizontal distance traveled is [katex] \sqrt{8}L [/katex]
Just ask: "Help me solve this problem."
A block of mass M1 travels horizontally with a constant speed v0 on a plateau of height H until it comes to a cliff. A toboggan of mass M2 is positioned on level ground below the cliff. The center of the toboggan is a distance D from the base of the cliff.
A rock is thrown at an angle of \( 42^\circ \) above the horizontal at a speed of \( 14 \, \text{m/s} \). Determine how long it takes the rock to hit the ground.
A curve with a radius of \( 125 \) \( \text{m} \) is properly banked for a car traveling \( 40 \) \( \text{m/s} \). What must be the coefficient of static friction \( (\mu_s) \) for a car not to skid on the same curve when traveling at \( 53 \) \( \text{m/s} \)?
An Olympic bobsled team goes through a horizontal curve at a speed of \( 120 \) \( \text{km/hr} \). If the radius of curvature is \( 10.0 \) \( \text{m} \), what is the apparent weight the crew experiences—express in terms of \( mg \)?
A drinking fountain projects water at an initial angle of \( 50^ \circ \) above the horizontal, and the water reaches a maximum height of \( 0.150 \) \( \text{m} \) above the point of exit. Assume air resistance is negligible.
(a) [katex] 2Mg [/katex], downward.
(b) [katex] v = \sqrt{2gL} [/katex].
(c) [katex] \sqrt{\frac{4L}{g}} [/katex].
(d) [katex] \sqrt{8}L [/katex]
By continuing you (1) agree to our Terms of Use and Terms of Sale and (2) consent to sharing your IP and browser information used by this site’s security protocols as outlined in our Privacy Policy.
| Kinematics | Forces |
|---|---|
| \(\Delta x = v_i t + \frac{1}{2} at^2\) | \(F = ma\) |
| \(v = v_i + at\) | \(F_g = \frac{G m_1 m_2}{r^2}\) |
| \(v^2 = v_i^2 + 2a \Delta x\) | \(f = \mu N\) |
| \(\Delta x = \frac{v_i + v}{2} t\) | \(F_s =-kx\) |
| \(v^2 = v_f^2 \,-\, 2a \Delta x\) |
| Circular Motion | Energy |
|---|---|
| \(F_c = \frac{mv^2}{r}\) | \(KE = \frac{1}{2} mv^2\) |
| \(a_c = \frac{v^2}{r}\) | \(PE = mgh\) |
| \(T = 2\pi \sqrt{\frac{r}{g}}\) | \(KE_i + PE_i = KE_f + PE_f\) |
| \(W = Fd \cos\theta\) |
| Momentum | Torque and Rotations |
|---|---|
| \(p = mv\) | \(\tau = r \cdot F \cdot \sin(\theta)\) |
| \(J = \Delta p\) | \(I = \sum mr^2\) |
| \(p_i = p_f\) | \(L = I \cdot \omega\) |
| Simple Harmonic Motion | Fluids |
|---|---|
| \(F = -kx\) | \(P = \frac{F}{A}\) |
| \(T = 2\pi \sqrt{\frac{l}{g}}\) | \(P_{\text{total}} = P_{\text{atm}} + \rho gh\) |
| \(T = 2\pi \sqrt{\frac{m}{k}}\) | \(Q = Av\) |
| \(x(t) = A \cos(\omega t + \phi)\) | \(F_b = \rho V g\) |
| \(a = -\omega^2 x\) | \(A_1v_1 = A_2v_2\) |
| Constant | Description |
|---|---|
| [katex]g[/katex] | Acceleration due to gravity, typically [katex]9.8 , \text{m/s}^2[/katex] on Earth’s surface |
| [katex]G[/katex] | Universal Gravitational Constant, [katex]6.674 \times 10^{-11} , \text{N} \cdot \text{m}^2/\text{kg}^2[/katex] |
| [katex]\mu_k[/katex] and [katex]\mu_s[/katex] | Coefficients of kinetic ([katex]\mu_k[/katex]) and static ([katex]\mu_s[/katex]) friction, dimensionless. Static friction ([katex]\mu_s[/katex]) is usually greater than kinetic friction ([katex]\mu_k[/katex]) as it resists the start of motion. |
| [katex]k[/katex] | Spring constant, in [katex]\text{N/m}[/katex] |
| [katex] M_E = 5.972 \times 10^{24} , \text{kg} [/katex] | Mass of the Earth |
| [katex] M_M = 7.348 \times 10^{22} , \text{kg} [/katex] | Mass of the Moon |
| [katex] M_M = 1.989 \times 10^{30} , \text{kg} [/katex] | Mass of the Sun |
| Variable | SI Unit |
|---|---|
| [katex]s[/katex] (Displacement) | [katex]\text{meters (m)}[/katex] |
| [katex]v[/katex] (Velocity) | [katex]\text{meters per second (m/s)}[/katex] |
| [katex]a[/katex] (Acceleration) | [katex]\text{meters per second squared (m/s}^2\text{)}[/katex] |
| [katex]t[/katex] (Time) | [katex]\text{seconds (s)}[/katex] |
| [katex]m[/katex] (Mass) | [katex]\text{kilograms (kg)}[/katex] |
| Variable | Derived SI Unit |
|---|---|
| [katex]F[/katex] (Force) | [katex]\text{newtons (N)}[/katex] |
| [katex]E[/katex], [katex]PE[/katex], [katex]KE[/katex] (Energy, Potential Energy, Kinetic Energy) | [katex]\text{joules (J)}[/katex] |
| [katex]P[/katex] (Power) | [katex]\text{watts (W)}[/katex] |
| [katex]p[/katex] (Momentum) | [katex]\text{kilogram meters per second (kgm/s)}[/katex] |
| [katex]\omega[/katex] (Angular Velocity) | [katex]\text{radians per second (rad/s)}[/katex] |
| [katex]\tau[/katex] (Torque) | [katex]\text{newton meters (Nm)}[/katex] |
| [katex]I[/katex] (Moment of Inertia) | [katex]\text{kilogram meter squared (kgm}^2\text{)}[/katex] |
| [katex]f[/katex] (Frequency) | [katex]\text{hertz (Hz)}[/katex] |
General Metric Conversion Chart
Example of using unit analysis: Convert 5 kilometers to millimeters.
Start with the given measurement: [katex]\text{5 km}[/katex]
Use the conversion factors for kilometers to meters and meters to millimeters: [katex]\text{5 km} \times \frac{10^3 \, \text{m}}{1 \, \text{km}} \times \frac{10^3 \, \text{mm}}{1 \, \text{m}}[/katex]
Perform the multiplication: [katex]\text{5 km} \times \frac{10^3 \, \text{m}}{1 \, \text{km}} \times \frac{10^3 \, \text{mm}}{1 \, \text{m}} = 5 \times 10^3 \times 10^3 \, \text{mm}[/katex]
Simplify to get the final answer: [katex]\boxed{5 \times 10^6 \, \text{mm}}[/katex]
Prefix | Symbol | Power of Ten | Equivalent |
|---|---|---|---|
Pico- | p | [katex]10^{-12}[/katex] | |
Nano- | n | [katex]10^{-9}[/katex] | |
Micro- | µ | [katex]10^{-6}[/katex] | |
Milli- | m | [katex]10^{-3}[/katex] | |
Centi- | c | [katex]10^{-2}[/katex] | |
Deci- | d | [katex]10^{-1}[/katex] | |
(Base unit) | – | [katex]10^{0}[/katex] | |
Deca- or Deka- | da | [katex]10^{1}[/katex] | |
Hecto- | h | [katex]10^{2}[/katex] | |
Kilo- | k | [katex]10^{3}[/katex] | |
Mega- | M | [katex]10^{6}[/katex] | |
Giga- | G | [katex]10^{9}[/katex] | |
Tera- | T | [katex]10^{12}[/katex] |
The most advanced version of Phy. 50% off, for early supporters. Prices increase soon.
per month
Billed Monthly. Cancel Anytime.
Trial –> Phy Pro
We created THE ultimate A.P Physics 1 course by simplifying everything so you can learn faster and score higher.
Try our free calculator to see what you need to get a 5 on the upcoming AP Physics 1 exam.
Understand you mistakes quicker.
Phy automatically provides feedback so you can improve your responses.
10 Free Credits To Get You Started
By continuing you agree to nerd-notes.com Terms of Service, Privacy Policy, and our usage of user data.
