Question

[Long answer Questions]
1. (a) Define land breeze and Sea breeze.
(b) How do they blow in coastal areas?
2. Define reflection of light. How can any polished or shiny surface acts as mirror.
3. Why are kidneys called major organs of excretory system? Explain briefly.
4. What is fuse? How does it prevent electric appliances from getting damaged?​

Answer 1

Question:-

1. (a) Define land breeze and Sea breeze.1)

(b) How do they blow in coastal areas?

2. Define reflection of light. How can any polished or shiny surface acts as mirror.

3. Why are kidneys called major organs of excretory system? Explain briefly.

4. What is fuse? How does it prevent electric appliances from getting damaged

Answer ;-

1)

a) land breeze :Land breeze blows during the night from land to sea and the land becomes cooler faster than the sea. The air above the sea becomes less dense (i.e. warmer) and rises. The cooler air from the land moves in to take its place.

Sea breeze: Sea breeze blows during the day and the land heats up faster than the sea.

b)During the day, the sun heats up both the ocean surface and the land. ... The wind will blow from the higher pressure over the water to lower pressure over the land causing the sea breeze. The sea breeze strength will vary depending on the temperature difference between the land and the ocean. At night, the roles reverse.

2)

• Reflection is when light bounces off an object. If the surface is smooth and shiny, like glass, water or polished metal, the light will reflect at the same angle as it hit the surface. This is called specular reflection.
• One way to change the direction of light is to let it fall on a shiny surface. For example, a shining stainless steel plate or a shining steel spoon can change the direction of light. The surface of water can also act like a mirror and change the path of light.

3)

• The excretory system in humans consists mainly of the kidneys and bladder. The kidneys filter urea and other waste products from the blood, which are then added to the urine within the bladder. Other organs, such as the liver, process toxins but put their wastes back into the blood. It is up to the kidneys to filter the blood so that toxic substances do not accumulate.
• The excretory system has other functions beyond removing waste products from the body. It is also crucial in maintaining internal homeostasis. Parts of the excretory system are also influenced by other body systems, such as the muscular system and skeletal system. For example, the kidneys secrete a hormone which tells the bones to produce more red blood cells

4)

• The fuse breaks the circuit if a fault in an appliance causes too much current to flow. This protects the wiring and the appliance if something goes wrong. The fuse contains a piece of wire that melts easily. If the current going through the fuse is too great, the wire heats up until it melts and breaks the circuit
• Fuses in plugs are made in standard ratings. The most common are 3 A, 5 A and 13 A. The fuse should be rated at a slightly higher current than the device needs

1. if the device works at 3 A, use a 5 A fuse
2. if the device works at 10 A, use a 13 A fuse