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Bholu and Golu are playing in a ground. They start running from the same point A in the ground and reach point B at the same time by following the paths marked 1 and 2 respectively as shown in figure. Which of the following is/are true for the given situation? As compared to Golu, Bholu covers a (a) longer distance but with a lower speed (b) longer distance with a higher speed (c) shorter distance with a lower speed (d) shorter distance with a higher speed

b) Longer distance with a higher speed The correct answer is option (b) Longer distance with a higher speed. Path 1 is longer than path 2. But... View Article

Paheli moves on a straight road from point A to point C. She takes 20 minutes to cover a certain distance AB and 30 minutes to cover the rest of distance BC. She then turns back and takes 30 minutes to cover the distance CB and 20 minutes to cover the rest of the distance to her starting point. She makes 5 rounds on the road the same way. Paheli concludes that her motion is (a) only rectilinear motion (b) only periodic motion (c) rectilinear and periodic both (d) neither rectilinear nor periodic

c) Rectilinear and periodic both Paheli is moving along a straight line with a fixed time period and returns to the starting point again. So... View Article

A piece of ribbon folded five times is placed along a 30 cm long measuring scale as shown in figure. The length of the ribbon is between (a) 1.15 m – 1.25 m (b) 1.25 m – 1.35 m (c) 1.50 m – 1.60 m (d) 1.60 m – 1.70 m.

(b): 1.25 m – 1.35 m According to the above figure, the five times folded ribbon piece is 5 times of folded ribbon is approximately- = (... View Article

Figure shows a measuring scale which is usually supplied with a geometry box. Which of the following distance cannot be measured with this scale by using it only once? (a) 0.1m (b) 0.15 m (c) 0.2 m (d) 0.05 m

The length of the measuring scale is 15 cm or 0.15 m. Formula used: 1 m = 100 cm The given distances in cm are: (a) 0.1 m = 0.1×100 = 10 cm... View Article

Which of the following does not express a time interval? (a) A day (b) A second (c) A school period (d) Time of the first bell in the school

The ‘time interval’ means that it is the difference between two instants of time. The time of the first bell in the school defines a... View Article

The distance between Delhi and Mumbai is usually expressed in units of (a) decametre (b) metre (c) centimetre (d) kilometre

(d) kilometre The International System of Units or SI units defines standard units for measurement of all physical quantities.A kilometer is a... View Article

Suggest an arrangement to store a U shaped magnet. How is this different from storing a pair of bar magnets?

A U magnet is stored in a wooden box with a soft iron placed at the edge. A bar magnet is kept in pairs with opposite poles facing the same... View Article

A bar magnet is cut into two pieces A and B, from the middle, as shown in the figure. Will the two pieces act as individual magnets? Mark the poles of these two pieces. Suggest an activity to verify your answer.

Yes, the two broken pieces A and B will act as individual magnets. A magnet will always have two poles – the North and South Pole. Hence,... View Article

Boojho kept a magnet close to an ordinary iron bar. He observed that the iron bar attracts a pin as shown in the figure What inference could he draw from this observation? Explain.

The iron bar can be used as a magnet as it has induced some magnetic properties from the bar magnet present there. The pin cannot be used as a... View Article

Suggest an activity to prepare a magnetic compass by using an iron needle and a bar magnet.

You can prepare a magnetic compass by following method: Place one needle on a wooden table Rub a magnet traverse the length of needle... View Article

The given figure shows a magnetic compass. What will happen to the position of its needle if you bring a bar magnet near it? Draw a diagram to show the effect on the needle on bringing the bar magnet near it. Also draw the diagram to show the effect when the other end of the bar magnet is brought near it.

As magnetic compass is made up of magnet only so it will follow the magnetic properties. When the North Pole of the magnet is brought near the... View Article

Describe the steps involved in magnetising an iron strip with the help of a magnet.

Here are the steps involved: Take a wooden table and place the desired iron strip to be magnetised on it. Take a bar magnet in such a manner... View Article

Three identical iron bars are kept on a table. Two out of three bars are magnets. In one of the magnet the North-South poles are marked. How will you find out which of the other two bars is a magnet? Identify the poles of this magnet.

Take the magnet with North-South poles marked. Keep it close with both the iron bars, and both will be attracted to it as both are magnetic. So... View Article

You are provided with two identical metal bars. One out of the two is a magnet. Suggest two ways to identify the magnet.

An object which is capable of producing magnetic field and attracting unlike poles and repelling like poles is known as magnets. Magnets can be... View Article

A toy car has a bar magnet laid hidden inside its body along its length. Using another magnet how will you find out which pole of the magnet is facing the front of the car?

To determine which pole of the magnet is facing the front of the car, use another magnet whose North & South pole is marked. Now bring any pole,... View Article

Four identical iron bars were dipped in a heap of iron filings one by one. Figure shows the amount of iron filings sticking to each of them. (a) Which of the iron bar is likely to be the strongest magnet? (b) Which of the iron bars is not a magnet? Justify your answer.

(a) In the given figure we can see that the iron bar in figure (a) attracts the maximum iron fillings. There (a) is the strongest magnet. (b)... View Article

Boojho dipped a bar magnet in a heap of iron filings and pulled it out. He found that iron filings got stuck to the magnet as shown in fig 13.4. (i) Which regions of the magnet have more iron filings sticking to it? (ii)What are these regions called?

The ends of the magnet will have more number of iron fillings attached to it. It is because the magnetic strength is maximum at the ends of... View Article

How will you test that ‘tea dust’ is not adulterated with iron powder?

We can use a magnet to check the adulteration in tea dust with iron powder. If we move the magnet over the tea dust, the iron powder will be... View Article

Paheli and her friends were decorating the class bulletin board. She dropped the box of stainless steel pins by mistake. She tried to collect the pins using a magnet. She could not succeed. What could be the reason for this?

The magnet attracts only those metals which have magnetic properties in them like iron, nickel, cobalt and so on. Here the pins are made up of... View Article

Fill in the blanks. (i) When a bar magnet is broken; each of the broken part will have _____ pole/poles. (ii) In a bar magnet, magnetic attraction is _ near its ends.

(i) When a bar magnet is broken; each of the broken parts will have two poles/poles. When the magnet is broken then each part of the broken... View Article

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