1. A)Determine how long, in seconds and minutes, it would take to consume 5.0 MJ of energy using a hair dryer rated at 1500w.
B) How many times could you dry your hair using the dryer described in (A)?
2. The largest bulldozer ever built had a mass of about 1.5*10^5kg and a blade 7.4m wide. its two engines had a total maximun power output of about1.7 MW. How much work (in megajoules) could this machie do each hour?
Physics question 20mark plz
2011-03-04 8:31 pm
回答 (2)
2011-03-05 1:23 am
✔ 最佳答案
1. A)Determine how long, in seconds and minutes, it would take to consume 5.0 MJ of energy using a hair dryer rated at 1500w.5MJ/1500W=1389W*hr/1500W = 0.926hr = 55min33.6s
B) How many times could you dry your hair using the dryer described in (A)?
It depends on you.
2. The largest bulldozer ever built had a mass of about 1.5*10^5kg and a blade 7.4m wide. its two engines had a total maximun power output of about1.7 MW. How much work (in megajoules) could this machie do each hour?
1.7MW*1hr = 6120MJ
2011-03-04 9:14 pm
收錄日期: 2021-04-16 12:31:11
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