Which of the following correctly describ | Class 10 Science Chapter Magnetic effects of Electric Current, Magnetic effects of Electric Current NCERT Solutions

When a 12 V battery is connected across an unknown resistor, there is a current of 2.5 mA in the circuit. Find the value of the resistance of the resistor.

Outline a project which aims to find the dominant coat colour in dogs.

Draw the structure for the following compounds.                

       (i)    Ethanoic acid             (ii)   Bromopentane*
       (iii)  Butanone                   (iv)   Hexanal.

*Are structural isomers possible for bromopentane?

A hot plate of an electric oven connected to a 220 V line has two resistance coils A and B, each of 24 Ω resistance, which may be used separately, in series, or in parallel. What are the currents in the three cases?

How is the sex of the child determined in human beings?

(a)  What property do all elements in the same column of the Periodic Table as boron have in common?
(b)  What property do all elements in the same column of the Periodic Table as fluorine have in common?

Calculate the number of electrons constituting one coulomb of charge.

A man with blood group A marries a woman with blood group O and their daughter has blood group O. Is this information enough to tell you which of the traits – blood group A or O – is dominant? Why or why not?

What is an homologous series? Explain with an example.

Why is variation beneficial to the species but not necessarily for the individual?

(a) Locate and name the water reservoirs in Figures16.1 (a) and (b).
(b) Which has an advantage over the other and why?

In question 44, what are the combinations of character in the F2 progeny? What are their ratios?

At the time of short circuit, the current in the circuit

(a) reduces substantially.
(b) does not change.
(c) increases heavily.
(d) vary continuously.

State Fleming’s left-hand rule.

What is the function of an earth wire? Why is it necessary to earth metallic appliances?

Leaves of a healthy potted plant were coated with vaseline. Will this plant remain healthy for long? Give reasons for your answer.

Give any two ways in which biodegradable substances would affect the environment.

Describe the process of urine formation in kidneys.

Choose the correct option.

The magnetic field inside a long straight solenoid-carrying current

(a) is zero.
(b) decreases as we move towards its end.
(c) increases as we move towards its end.
(d) is the same at all points.

How is the sex of the child determined in human beings?