CDS General Knowledge 2021 Question Paper

Where should an object be placed in front of a convex lens to get a real and enlarged image of the object ?

The magnetic field lines inside a current carrying long solenoid are in the form of

A ray of light travelling from a rarer medium to a denser medium

An electric circuit is consisting of a cell, an ammeter and a nichrome wire of length $l$. If the length of the wire is reduced to half ($l/2$), then the ammeter reading

What is the effect of pressure of a human body on sand ?

An athlete completes one round of a circular track of diameter $100$ m in $20$ s. What will be the displacements after $1$ minute and $10$ s, respectively ?

Which of the following statements about universal indicator is/are true ?

1. It is a mixture of several indicators.
2. It shows different colours at different concentrations of hydrogen ions in solution.
3. It helps to determine the strength of given acid and base in titration.
   Select the correct answer using the code given below :

Which of the following carbon allotropes is/are good conductor(s) of electricity ?

Select the correct answer using the code given below :

What is the approximate percentage of carbon in the Earth's crust ?

When copper reacts with moist carbon dioxide (${\text{CO}}_2$) in air, it forms a green coating of which one of the following compounds ?