Do you want to be really good at problem-solving? The key is to get plenty of practice.
Here is one of the problems from i-want-to-study-engineering.org, a practice website designed for students who plan to apply for Engineering at top universities:
- the average distance between the earth and the moon is 3.8 x 108 m,
- on average, it takes the moon 29 days to go round the earth,
- the approximate value of the universal gravitational constant
G= 6.7 x 10-11m3kg-1s-2.
estimate the mass of the earth.
Is the answer:
- approximately 5 x 1023kg?
- approximately 6 x 1024kg?
- approximately 7 x 1025kg?
- approximately 42kg?
- None of the above?
For hints, topic information and answers, see the problem page itself, or for more problems (there are more than 200 available), see the problem index.