Am i correct in getting a low value?

  • Thread starter madglover
  • Start date
  • Tags
    Value
In summary, a crane used its petrol engine to lift a beam weighing 103 kg to a certain height, releasing 1 MJ (106 J) of chemical potential energy. 85% of this energy was transferred as heat to the air, while the internal energy of the engine increased by 4.0×104 J. The superstructure of the crane and the beam did not experience any change in energy, except for the superstructure's increase in gravitational potential energy by 104 J. The crane was at rest before and after the lifting process. Assuming all the energy used by the crane was solely for lifting the beam, the fuel cost would be calculated based on the calorific value of the fuel (43 MJ kg−1), its
  • #1
madglover
8
0
A crane uses its petrol engine to lift a beam of mass 103 kg by height
h. The fuel burned loses 1 MJ (106 J) of chemical potential energy, 85%
of this being transferred by heating to the air. The internal energy of the
crane’s engine increases by 4.0×104 J, while that of the crane’s superstructure
and the beam is unchanged. The crane’s superstructure (not engine or fuel)
increases in gravitational potential energy by 104 J. Everything is at rest
before and after. Assume all transfer by working out of the crane is used to
lift the beam.
(a) [10 marks] The calorific value of the fuel is 43 MJ kg−1, its density is 737
kg m−3 and it costs 90p per litre (there are 1000 litres in 1 m3). What was
the fuel cost of raising the beam?
 
Physics news on Phys.org
  • #2
I tried to apply lots of the basic energy conservations laws but get stuck when approaching an answer making me very depressed. Sympathy work well on here?
 
  • #3
Lets see your working so far and where you are are stuck.
 

Related to Am i correct in getting a low value?

1. What factors can contribute to a low value in my research?

There are several factors that could contribute to a low value in your research. These may include errors in measurement or data collection, limitations in the study design, or variability in the data. It is important to carefully examine these factors and determine how they may have influenced your results.

2. Should I be concerned about a low value in my research?

A low value in your research may indicate that there is a problem with your methodology or data. However, it is important to consider the context and significance of your findings before becoming overly concerned. It may be helpful to consult with colleagues or seek advice from a mentor to gain a better understanding of your results.

3. Can a low value be a result of chance or random variation?

Yes, a low value can be a result of chance or random variation. In scientific research, it is common to have some degree of variability in data. This is why it is important to use statistical tests to determine the significance of your results and to account for any chance variations.

4. How can I improve the value in my research?

If you have identified a low value in your research, there are several steps you can take to improve it. Some options may include collecting more data, using more precise measurement techniques, or adjusting your study design. It may also be helpful to collaborate with other researchers or seek feedback from experts in your field.

5. Can a low value still lead to valuable insights?

Yes, a low value in your research can still lead to valuable insights. It is important to look beyond the numerical result and consider the underlying patterns and trends in your data. Even if the value is lower than expected, it may still provide important information about your research topic and contribute to the overall body of scientific knowledge.

Similar threads

Replies
2
Views
1K
  • Introductory Physics Homework Help
Replies
5
Views
1K
  • Introductory Physics Homework Help
Replies
4
Views
1K
  • Engineering and Comp Sci Homework Help
Replies
1
Views
2K
  • Engineering and Comp Sci Homework Help
Replies
9
Views
7K
  • Engineering and Comp Sci Homework Help
Replies
7
Views
2K
Replies
58
Views
3K
  • Mechanical Engineering
Replies
2
Views
8K
  • Introductory Physics Homework Help
Replies
6
Views
6K
  • Introductory Physics Homework Help
Replies
2
Views
3K
Back
Top