Why must a room air conditioner be placed in a window ? Why can't it just be set on the floor and plugged in ?

Why can’t HCl acid be used to acidify KMnO_(4) solution ?

Mr. Dogra lives in a very old house. The electric wiring in this house was done more than 50 years ago. Mr. Dogra purchased an air conditioner recently. One day Mr. Dogra was sitting in a closed room with all his family members with air conditioner switched on. A geyser was also working on the same socket as the air conditioner. Suddenly, everyone in the room heard a little explosion and saw that the electric wires in the air conditioner socket had caught fire. Mr. Dogra was so shocked that he did not know what to do. Mr. Dogra's son Rajesh who is studying in Class X rushed out of the room and put off the main switch quickly. Before Mr. Dogra could call the Fire Brigade, Rajesh extinguished the fire with the help of a fire extinguisher which he had made in the school. An electrician was called. When he checked the main fuse, he found that someone had put a thick copper wire in the main fuse instead of proper fuse wire. The electrician changed the whole wiring of the house by using good quality wires and fixed a proper fuse wire in the main fuse. He also made separate circuit for geyser and provided separate fuses for all the circuits. (a) Why did the electric wires catch fire ? (b) What is the condition of using an air conditioner and a geyser on the same socket known as ? (c) Why did the fuse not blow off ? (d) What would you recommend in place of old porcelain fuse holders in the house to project the wiring more efficiently ? (e) What values are displayed by Mr. Dogra's son Rajesh in this whole episode ?

The length of longest pole that can be placed in the floor of a room is 12 m and the length of longest pole that can be placed in the room is 15 m. The height of the room is

The length of longest pole that can be placed on the floor of a room is 12 m and the length of longest pole that cn be placed in the room is 15 m . The height of the room is :

Why can't copper displace zinc from its salt solution?