Physics homework help that sets up the problem with you
Stuck on a physics problem? Usually the hard part is the setup: what is known, which direction is positive, and which equation connects them. This prompt has your agent list the givens, describe a free-body or motion diagram, choose the equation and say why, solve with units, and then sanity-check the answer against common sense.
The prompt
- Help me with this physics problem: [PROBLEM OR PHOTO]. My course is [COURSE] and we use [g VALUE AND SIGN CONVENTION]. My attempt: [MY WORKING]. First list the known and unknown quantities with units, then describe the diagram (forces or motion) and pick a positive direction. Say which equation or principle fits (kinematics, Newton's laws, energy, momentum) and why the others do not. Solve it algebraically first, then plug in numbers with units, and check the arithmetic by calculation. Finish with a sanity check (sign, size, units) and one similar problem for me to try, without its answer.
What to change
- [PROBLEM OR PHOTO]: Type the problem or attach a photo, including any diagram from the book.
- [COURSE]: E.g. "AP Physics 1", "GCSE Physics", "University Physics I (calculus-based)".
- [g VALUE AND SIGN CONVENTION]: E.g. "g = 9.8 m/s², up is positive" or "g = 10 N/kg". Write "default" if you don't know.
- [MY WORKING]: Type your steps or attach a photo. Write "no idea where to start" if so.
Example result
- Problem
- A 2.0 kg box slides from rest down a frictionless ramp. The ramp is 8.0 m long and rises 5.0 m. How fast is the box moving at the bottom? Use g = 9.8 m/s².
- Knowns and unknowns
- • m = 2.0 kg
- • Height h = 5.0 m (vertical drop)
- • Ramp length L = 8.0 m
- • Starts from rest: v0 = 0
- • No friction
- • Unknown: v at the bottom
- Diagram
- Forces on the box: gravity (mg, straight down) and the normal force (perpendicular to the ramp). No friction, so the normal force does no work.
- Which principle and why
- Conservation of energy. We know heights and speeds, not time, and there is no friction, so mechanical energy is conserved. Kinematics would also work, but we would need the acceleration along the slope first, which is an extra step.
- Solve with symbols first
- • mgh = (1/2)mv²
- • The mass cancels: v = sqrt(2gh)
- Plug in numbers
- v = sqrt(2 × 9.8 m/s² × 5.0 m) = sqrt(98 m²/s²) = 9.9 m/s
- Sanity check
- • Units: sqrt(m²/s²) = m/s. Correct.
- • Size: an object dropped 5 m straight down also reaches 9.9 m/s. On a frictionless ramp the speed depends only on height, so the same answer makes sense.
- • The 2.0 kg and the 8.0 m length were not needed. Physics problems often include extra information.
- Your attempt
- You used h = 8.0 m, the ramp length. Energy depends on the vertical height, so use 5.0 m.
- Your turn
- A 0.50 kg ball is thrown straight up at 12 m/s. How high does it rise? Reply with your setup and answer.
How to do it with todo.is
- Fill in the problem, your course, the g value your class uses and your attempt.
- Send it in todo.is on the Today screen or to your agent on WhatsApp or Telegram, with a photo if the problem has a diagram.
- Your agent replies with the setup, the reasoning for the equation, a solution with units and a sanity check.
- Try the practice problem and reply. Ask for "a sketch of the diagram as an image" if you want to see it drawn.
Tips for a better result
- Solve with symbols before numbers. You can see what cancels (often the mass) and spot errors early.
- Pick a positive direction and write it down. Most sign errors in kinematics come from switching halfway.
- If a problem gives time, use kinematics; if it gives heights and speeds but no time, try energy first.
- Ask your agent to plot position and velocity against time (PNG) for motion problems. Graphs show what the numbers mean.
physics homework help: FAQ
- What physics topics does it cover? Kinematics, forces and Newton's laws, energy and work, momentum, circular motion, waves, electricity and circuits, magnetism, and basic thermodynamics and optics, from high school to first-year university.
- Can it handle calculus-based physics? Yes. Say "calculus-based" in the course field and it uses derivatives and integrals where they fit, and checks the math in Python.
- Can it draw the free-body diagram? It describes every force in words, and on request makes a simple diagram image. Check that the arrows match the description before you copy it.
- Should I use g = 9.8 or 9.81 or 10? Use whatever your teacher or exam board uses. Put it in the prompt so the numbers match your answer key.
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