1. The centripetal force required for a car to bicyle to go round a circular curve depends on

Centripetal force (Fc) is required to keep a vehicle moving in a circular path and is given by the formula: Fc=mv2/r where: • m is the mass of the vehicle, • v is the speed of the vehicle, • r is the radius of curvature. From the equation, we can see that centripetal force depends on both the speed of the vehicle (v) and the radius of curvature (r).

2. The angle of projection for a projectile to cover maximum range is

3. The angle of projection for a projectile to cover maximum range is

4. The geocentric theory is given by

The geocentric theory, which states that Earth is the center of the universe, was proposed by Claudius Ptolemy.

5. A rocket is not a projectile until its

A rocket is not a projectile until its propellant fuel is completely burnt because, before that, it is still being propelled by thrust. Once the fuel is exhausted, it follows a projectile motion under gravity.

6. The molecular range is of the order of

The molecular range refers to the distance up to which molecular forces act. It is typically in the range of 10⁻⁸ cm (or 10⁻¹⁰ m), which is approximately the size of molecules.

7. The centripetal force around the circular path depends upon

8. The force between a satellite and the earth which acts as a centripetal force keeping the satellite in orbit is

The force that keeps a satellite in orbit around the Earth is the gravitational force. This force acts as the centripetal force, continuously pulling the satellite towards the Earth, preventing it from flying off into space. According to Newton’s Law of Universal Gravitation: F = GMm/r sq where: F = gravitational force G = gravitational constant M = mass of the Earth m = mass of the satellite r = distance between the centers of the Earth and the satellite This force ensures that the satellite follows a stable orbit around the Earth. ​

9. A bullet shot from a rifle is an example of

A bullet shot from a rifle follows a curved trajectory due to the influence of gravity, making it a projectile. A projectile is any object that is given an initial velocity and then moves under the influence of gravity alone. The motion of the bullet can be analyzed using the equations of projectile motion, where: The horizontal motion is uniform (constant velocity). The vertical motion is uniformly accelerated due to gravity. This is a classic example of projectile motion in physics.

10. The unit of surface tension is

Surface tension is defined as the force per unit length acting along the surface of a liquid. Its SI unit is Newton per meter (N/m or Nm⁻¹), which is derived from the formula: Surface Tension = Force / Length ​

11. The formula to calculate centripetal force is

12. The Helio Centric theory is given by

The Heliocentric Theory, which states that the Sun is at the center of the universe and the planets revolve around it, was proposed by Nicolaus Copernicus in the 16th century. Before Copernicus, the Geocentric Theory (Earth at the center) was widely accepted. His work "De revolutionibus orbium coelestium" (On the Revolutions of the Celestial Spheres) published in 1543, challenged this view. Later, Johannes Kepler refined the model with his laws of planetary motion.

13. X sq = ky. This is the equation of a

14. Kepler’s first law of planetary motion is also called

Kepler's First Law states: "The orbit of a planet around the Sun is an ellipse, with the Sun at one of its foci." This law is called the Law of Orbits because it describes the shape of planetary orbits. It disproved the earlier belief that planets move in perfect circles around the Sun. The other Kepler's laws are: Second Law (Law of Areas): A planet sweeps out equal areas in equal time intervals. Third Law (Law of Periods): The square of a planet’s orbital period is proportional to the cube of its semi-major axis.

15. The air resistance on freely failing body depends upon

Air resistance on a freely falling body depends on its shape. Streamlined objects face less resistance, while broader shapes experience more. Other factors include speed, surface area, and air density.

16. Rain drops assume spherical shape due to

Rain drops take a spherical shape due to surface tension, which minimizes surface area. This cohesive force between water molecules pulls the drop inward, forming a shape with the least energy configuration.

17. The principle used in the centrifuges is

Centrifuges work by spinning a sample rapidly, causing denser particles to move outward due to centrifugal force, aiding in separation processes like blood component separation or sedimentation of particles.

18. The time period of Jupiter is

Jupiter takes approximately 11.86 Earth years to complete one orbit around the Sun. This is due to its greater distance from the Sun compared to Earth.

19. The unit of angular velocity its

Angular velocity is measured in radians per second (rad/s), which represents the rate of change of angular displacement over time.

20. The relation between time of ascent and time of descent in the case of bodies moving under gravity is

For a body moving under gravity (ignoring air resistance), the time taken to rise to the highest point (ascent) is equal to the time taken to fall back to the initial position (descent). This follows from the symmetry of motion under uniform acceleration due to gravity.