The diagram shows a soft iron core coiled with wire.

When the switch is turned on, iron nails are attracted. Which of the following ways, will make the soft iron core to attract all the iron nails?

 

A car is accelerating on a road in the direction shown in the figure. The tyre shown is connected to the engine. In which direction is the force of friction exerted by the road on the tyre?

Statement $1$: The size of a hydrogen balloon increases as it rises in the air.

Statement $2$: The material from which the balloon is made can be easily stretched. 

Anju walks $8 \mathrm{m}$ to the east, then $6 \mathrm{m}$ to the south, then $8 \mathrm{m}$ to the west, and finally $6 \mathrm{m}$ to the north. What is the distance covered and displacement of Anju?

Deepak put twenty ice cubes of the same volume into four containers packed with different materials. He recorded the time taken for the ice to melt in each case. The table shows his results. Which of these boxes should he choose to carry ice that he needs to take to a friend's house $120 \mathrm{km}$ away?

A positively charged object attracts a suspended light conducting ball. The light conducting ball can be:

The terminals of a battery are joined by a length of resistance wire. Which change, on its own will decrease the current through the battery?

The figure gives the speed-time graph of the motion of a car. What is the ratio of the distance travelled by car during the last two seconds to the total distance travelled in seven seconds?