Question
What is the main principle behind the working of an
electric motor?Solution
An electric motor works on the principle of electromagnetic induction. When a current carrying conductor is placed in a magnetic field, a force acts on it, resulting in motion. This is explained by Fleming's left hand rule. The magnetic field and electric current interact to produce mechanical energy.
The ratio of P :Q is 3 : 5 and that of Q : R is 4 : 7. If P equals 2400, then what is the value of R?
A student bought 10 pencils and 8 pens at Rs 150. He sells pencil at 4%profit and pen at 7%profit. Overall, he gains Rs 9 Find the cost price of each pe...
An amount of money is divided among L, M and N in the ratio of 3:4:7, respectively. If the amount received by N is Rs.6000 more than the amount received...
The ratio between the number of books and pencils is 7:6 and the ratio of cost of per book and pencil is 3:2 then find the percentage by which total cos...
Find 'X' if the below three numbers are in proportion.
2.6, 1.3, X
Population of a town is 1,02,000. If number of the male increase by 7% and Females increase by 10% then the population of town would increase by 9.5 %. ...
In a class of 455 students, 255 are girls and remaining are boys. Among boys, the ratio of number of boys who are wearing caps to those who are not wear...
- In a company, 60% of the number of girls is equal to two - third of the total number of boys. When 40 new girls joined the company, then 25% of the number ...
If x runs are second by Rohit, y runs by Shreyas and z runs by Virat, then x : y = y : z = 4:3. If total number of runs scored by Rohit, Shreyas and Vir...
What is the fourth proportion of 18, 20 and 23?
