Ans 1: (Master Answer)
Alpha particles leaves the nucleus of an unstable atom at a speed of 16,000 kilometres per second, around a tenth the speed of light.
Beta particles travel at a speed of 270,000 kilometres per second, around 98% of speed of light.
Gamma particles travel at the speed of light.
X changes to Y when it is cooled down.
Select the correct option about the arrangement of molecules in X and Y.
Achin conducted an experiment to find out the amount of light that can pass through three different materials, a clear plastic sheet, a cardboard and a piece of tracing paper. All the materials have the same thickness. He shone a torch on the three materials and used a light sensor to measure how much light has passed through each of them. Which of the following graphs most likely shows the amount of light that has passed through each material?
Abhinav walked 2 km West of his house and then turned South covering 4 km. Finally, he moved 3 km towards East and then again 1 km West. How far is he from his initial position?
A 2 km
B 4 km
C 9 km
D 10 km
I didnt understand this
Read the passage carefully and answer Q.
An 8000 kg engine pulls a train of 5 wagons, each of 2000 kg, along a horizontal track. If the engine exerts a force of 40000 N and the track offers a frictional force of 5000 N. The force of wagon 1 on wagon 2 is
(A) 28000 N
(B) 18000 N
(C) 10000 N
(D) 20000 N
The six items are all filled with equal amounts of air. What is likely to happen when similar amounts of air are pumped into each of the objects ?
(i) The two balloons will be bigger in size as more air gets in.
(ii) The air filled ball and tyre will also be bigger in size as more air gets in.
(iii) The gas cylinder and oxygen tank will not change their size but the air in them will be compressed.
(A) (ii) only
(B) (i) & (iii)
(C) (iii) only
(D) (i) & (ii).