List of top Science Questions

What is the acceleration of free fall?
What do we call the gravitational force between the earth and an object?
The speed-time graph for a car is shown is Fig.
The speed-time graph for a car
 
  1. Find how far does the car travel in the first 4 seconds. Shade the area on the graph that represents the distance travelled by the car during the period. 
  2. Which part of the graph represents uniform motion of the car?
Amit buys few grams of gold at the poles as per the instruction of one of his friends. He hands over the same when he meets him at the equator. Will the friend agree with the weight of gold bought? If not, why? [Hint: The value of g is greater at the poles than at the equator.]
Why will a sheet of paper fall slower than one that is crumpled into a ball?
State which of the following situations are possible and give an example for each of these: 
  1. an object with a constant acceleration but with zero velocity 
  2. an object moving with an acceleration but with uniform speed. 
  3. an object moving in a certain direction with an acceleration in the perpendicular direction.
Gravitational force on the surface of the moon is only \(\frac{1}6\) as strong as gravitational force on the earth. What is the weight in newtons of a 10 kg object on the moon and on the earth?
Make a comparison and write down ways in which plant cells are different from animal cells.
How is a prokaryotic cell different from a eukaryotic cell?
Define the term “tissue”.
What would happen if the plasma membrane ruptures or breaks down?
How many types of elements together make up the xylem tissue? Name them.
What would happen to the life of a cell if there was no Golgi apparatus?
Which organelle is known as the powerhouse of the cell? Why?
Where do the lipids and proteins constituting the cell membrane get synthesized?
How are simple tissues different from complex tissues in plants?
How does an Amoeba obtain its food?
What is osmosis?
Carry out the following osmosis experiment: Take four peeled potato halves and scoos each one out to make potato cups. One of these potato cups should be made from a boiled potato. Put each potato cup in a trough containing water. Now, 
  1. Keep cup A empty 
  2. Put one teaspoon sugar in cup B 
  3. Put one teaspoon salt in cup C 
  4. Put one teaspoon sugar in the boiled potato cup D. Keep these for two hours. Then observe the four potato cups and answer the following: 
  1. Explain why water gathers in the hollowed portion of B and C. 
  2.  Why is potato A necessary for this experiment? 
  3. Explain why water does not gather in the hollowed-out portions of A and D.
Differentiate between parenchyma, collenchyma and sclerenchyma on the basis of their cell wall.
Which type of cell division is required for growth and repair of body and which type is involved in formation of gametes?
An athlete completes one round of a circular track of diameter  \(200 \;m\) in \(40 \;s\). What will be the distance covered and the displacement at the end of \(2\) minutes \(20\) \(s\)?
Which of the following has more inertia: (a) a rubber ball and a stone of the same size? (b) a bicycle and a train? (c) a five-rupees coin and a one-rupee coin?
A battery lights a bulb. Describe the energy changes involved in the process.
Identify the type of tissue in the following:
skin, bark of tree, bone, lining of kidney tubule, vascular bundle.