How do you solve this physical question

Instructions for solving physical problems

Step sequence for solving technical tasks:

Factual problems in physics (as in mathematics) are solved in 4 steps:

  1. given: - Acquisition of all important given quantities.
    • Read the task carefully and mark all the important parameters with a marker.
    • Enter sizes with formula symbols, value and unit under given.
  2. searched: - Detecting the physical quantity you are looking for.
    • Mark the size you are looking for with a marker in a different color.
    • Enter sizes with formula symbols, value and unit under searched.
  3. Solution: - Calculate the desired physical quantity with the help of the correct formula
    • Note it must always be there: FORMULA - FORMULA inserted - RESULT with unit
    • Find the correct formula from the table of contents with the help of the table of contents.
    • If necessary, convert sizes into other units.
    • Insert the given values ​​with units in the formula.
    • Calculate with a calculator.
    • Enter the result with the correct unit.
  4. Answer sentence: - Write an answer phrase related to the question
    • Use the result to answer the question asked in the exercise.

Example 1 - we work together ...

Susi pushes a shopping trolley through a supermarket with a force of 220 N. It covers a distance of 80 m. Calculate the mechanical work (pushing work) that Susi did in the supermarket.

For the first example:

Here is the solution again for example 1 ->


Example 2 - we work together again ...

A crane lifts a pallet onto a ship in 1.5 minutes. It does 90 kJ of mechanical work. How big is the mechanical work done by the crane.

For the second example:


Example 3 - Try it yourself ...

A conveyor belt in the airport transports suitcases. A suitcase covers a distance of 180 meters. This takes him 2 minutes. Calculate the speed of the conveyor belt in meters per second. (Note - you still have to convert the minutes into seconds.

Here are the solutions for example 2 and 3 ->


In grade 7, the technical tasks are usually more complex. However, they are solved using the same sequence of steps. The complex task is broken down into sub-tasks and then solved in 4 work steps. Here is an example to practice with, of course with a solution

Example 4 - a complex task with a lot of explanation

A crane lifts a box with a mass of 150 kg to a height of 12 m in 30 s.

  1. Calculate the mechanical work (lifting work) that the crane does. (Note that the mass is given.)
  2. Calculate the mechanical power that the crane performed.

Here is the worksheet to practice with ->

Here is the solution to the complex task ->