1) In the hare-tortoise race, the hare ran for 2 min at a speed of 7.5 km/h, slept for 56 min, and again ran for 2 min at a speed of 7.5 km/h. Find the average speed of the hare in the race. 2) The maximum speed of a train is 80 km/h. It takes […]

## Thrust and Pressure Numericals for class 9 [solved]

In this post, we have solved a set of Thrust and Pressure Numericals for class 9. Thrust and Pressure Numericals for class 9 (Q1) Calculate the pressure exerted by a dancer weighing 600N standing on a single heel of area 1 cm2. The surface of the dance floor is broken by pressures over 5 MPa. […]

## Motion Numericals Class 9 Physics – questions & answers

This page consists of interesting Motion Numericals of class 9 physics. These Numericals & questions are based on equations of motion (suvat equations). The solved answers to the Physics Numericals for class 9 motion are provided with step-by-step explanations. Motion class 9 Numericals | Physics Numericals for class 9 motion 1) A speedboat has an […]

## Potential Difference Numerical problems

Potential Difference Numerical problems – In this post, we will solve selected numerical problems on Potential Difference (PD). To solve these PD numericals we will use concepts and formulas of electric potential and PD.

## p=iv practice problems | p=iv problems using electric power formula

how to solve a set of p=iv practice problems or p=iv problems using the electric power formulas (P = IV and P = I2R). numerical, physics

## Numerical problem – a ball thrown vertically upwards

When a ball is thrown vertically upwards, it goes through a distance of 19.6 m. Find the initial velocity of the ball and the time taken by it to rise to the highest point.

## Energy Stored in Capacitors – numerical worksheet

In this post, we have presented a collection of numerical problems on Energy Stored in Capacitors in the form of a numerical worksheet. This is good for grade 11 and grade 12 students. Energy Stored in Capacitors – worksheet | numerical problems Q1: A large capacitor has plates with areas of 1.5 m2 that are […]

## Parallel-Plate Capacitors – numerical worksheet

In this post, we have presented a collection of numerical problems on Parallel-plate capacitors in the form of a numerical worksheet. This is good for grade 11 and grade 12 students. Parallel-Plate Capacitors – worksheet | numerical problems Q1 ) A synthetic sweater becomes statically charged by friction. The sweater and the skin beneath it […]

## Grade 12 Physics (South African curriculum – physical science paper 1) – Assignment

QUESTION 1A helicopter is flying vertically up at an unknown constant velocity. An object is dropped from the helicopter when it is exactly 88 m above the ground. The object takes 1.5 s to reach its maximum height from the time it was released. Air friction is ignored. 1.1) Calculate the magnitude of the velocity […]

## electrostatics – Worksheet 1 problem solution (Q4)

4) A positively charged object Q is placed as shown in the sketch. The potential difference between two points A and B is 4 x 10-4 V. (a) Calculate the change in electrical potential energy of a +2nC charge when it moves from A to B.(b) Which point, A or B, is at the higher […]

## electrostatics – Worksheet 1 problem solution (Q3)

3 ) A charge of +5nC is moved by a distance of 4 cm against a uniform electric field of magnitude 2 x 1012 NC-1 from A to B. (a) Calculate the work done in moving the charge from A to B.(b) The charge is now released and returns to A. Calculate the kinetic energy […]

## electrostatics – Worksheet 1 problem solution (Q2)

Question 2) In the picture below, X is a small negatively charged sphere with a mass of 10kg. It is suspended from the roof by an insulating rope which makes an angle of 60o with the roof. Y is a small positively charged sphere that has the same magnitude of charge as X. Y is […]

## electrostatics – Worksheet 1 problem solution (Q1)

1 ) Determine the electrostatic force and gravitational force between two electrons 1ºA apart (i.e. the forces felt inside an atom) [ here is the complete worksheet: electrostatics worksheet 1 ] Solution: Getting everything into S.I. units: The charge on an electron is 1.6×10-19C, the mass of an electron is 9.11 x 10-31kg, and 1ºA=1 […]

## Electrostatics Numericals Class 12 – solved questions, worksheet 1

In this post, we publish a worksheet containing a bunch of numerical problems from the Electrostatics chapter of HS physics. This set of Electrostatics Numericals for class 12 includes problems based on Coulomb’s force or electrostatic force, electric field, electric potential, electric potential energy, etc. Links to the solutions to the numerical problems will be […]

## Electrical Potential difference & mechanical work – numerical problems

The potential difference between two points in a circuit is the electrical energy per unit charge. When this electrical energy is converted into other forms of energy (thermal, light, mechanical, etc.), then it can be expressed as: potential difference =electrical energy converted into other forms/charge passingor, potential difference =work done/charge passing [as energy is the […]

## The motion of a charged particle in an electric field between two parallel plates

In this post, we will analyze different scenarios of the motion of a charged particle in an electric field between two parallel plates. Effect of electric fields on the motion of charged particles A charged particle in an electric field experiences a force and therefore tends to accelerate. If the particle is stationary the magnitude […]

## Numerical problem based on Capillary Rise & Capillarity

Here, we will solve a Numerical problem based on Capillary Rise & Capillarity. Numerical assignment (on Capillary Rise & Capillarity) solved 1) A glass tube of radius 0.4 mm is dipped vertically in the water. Find up to what height, the water will rise in the capillary. If the tube is inclined at an angle […]

## Numerical problems on electric potential energy

In this post, we will solve Numerical problems on electric potential energy. [Electric potential energy is also known as electrical potential energy] Numerical Problem based on electrical potential energy Suppose a charge of 5.60 x 10−3 C is placed at one end of the 8.37 km sandcastle, while an unspecified charge is placed at the […]

## Numerical problem based on electric field between charged parallel plates

Here, we will solve a set of Numerical Problems based on the formula of the electric field between two charged parallel plates. Numerical Problem (Physics) – based on the formula of the electric field between two charged parallel plates 1 ) A cathode-ray-tube (CRT) computer monitor accelerates electrons between charged parallel plates (Figure 1).These electrons […]

## Mathematical Formulas

In this post, we present images (infographics) that contain a set of Mathematical Formulas. This will be a ready reckoner for educational understanding purposes. Quadratic formula Geometry – (area, volume) Trigonometry Triangle Series expansions Derivatives Integrals Disclaimer: (please let us know if you find any typos or errors. This post and its contents are For […]

## Fundamental Constants (Physics & Chemistry)

In this post, we present an image (infographics) that contains a set of fundamental constants used in Physics and Chemistry with their symbols and values. This will be a ready reckoner for constants and their values. A few such constants available in this infographics are Atomic mass unit, Avogadro’s number, Coulomb constant, Gas constant, Permittivity […]

## Small Angle Approximations (for physics derivations and numerical problems)

For very small angles, you can approximate values for the sine, cosine, or tangent. This is useful when calculating the fringe separations in interference patterns. When θ is measured in radians, a small angle segment approximates to s/r where s is the arc length and r is the radius. In other words, for a small […]

## Potential difference (Electrical) worksheet – with solved numerical

Potential difference (Electrical) Worksheet Questions Q1. How much is the work done in moving a charge of 4 C across two points having a potential difference of 24 V? Q2: What is the work done in moving a charge of 2 C from a point at 220 V to a point at 120 V? Q3: […]

## Coefficient of Restitution – definition, formula, numerical

In this post, we will cover the definition and formula of the coefficient of restitution. We will also see how types of collision can be determined from the value of the coefficient of restitution. We will also solve a numerical problem using the formula of the coefficient of restitution. What is the Coefficient of Restitution? […]

## How to find The Angle Between Two Vectors

In this post, we will see how to find out the angle between two vectors. Say A and B are 2 vectors, where A =Ax i + Ay j + Azk and B = Bx i + By j + Bzk If we take the cross product of these 2 vectors, then we can write: […]

## Orbital speed & Escape speed – worksheet

This worksheet contains numerical problems on Orbital speed & Escape speed. 1) a) Confirm that the escape speed from the Earth’s surface is 11.2 km s−1.b) Explain why all masses have the same escape speed.c) Determine the escape speed from a planet that had twice the radius of Earth, but the same density. 2) The […]

## Carnot cycle processes of Carnot engine

The Carnot cycle represents the cycle of processes for a theoretical heat engine with the maximum possible efficiency. Such an idealized engine is called a Carnot engine. Here in this post, we present a brief idea of the Carnot cycle processes, Carnot engine efficiency, and also we solve here a numerical problem related to the […]

## Lami’s theorem to solve numerical problems of electrostatics

Lami’s theorem is used to solve numerical problems of electrostatics when electrostatic forces are in equilibrium. To solve some questions of electrostatics, Lami’s theorem is very useful. Lami’s theorem (when forces are in equilibrium) If three forces are in equilibrium, as shown in figure 1, it means that F1 + F2 + F3 = 0, […]

## Fluid flow – Important Formulas (for class 11)

This post presents a list of facts and formulas from the Fluid flow chapter of class 11 (grade 11) physics. formulas from the Fluid flow chapter of class 11 1 ) Pressure is the force per unit area exerted by a fluid on its surroundings: P = F/A Its SI units are pascals where 1 […]

## P–V diagram & calculation of work done

In this post, we will discuss how the P-V diagram can help us to calculate the work done by a system or on a system. We will derive the equation of work done in terms of pressure and volume. We will solve a few numerical problems as well based on P-V diagrams. Setup to get […]

## Explosion and Conservation of Momentum

An explosion can be thought of as a single object separating into two or more fragments. In this post, we will see if the law of conservation of momentum is maintained during an explosion. We will solve related numerical problems as well. Some familiar examples of explosions are: a bomb blowing into fragments a bullet […]

## Gravitational Potential Numericals – solved worksheet (numerical)

In this post, find Gravitational Potential Numericals in a solved worksheet (numerical). And, we will solve a bunch of numerical problems (Questions and answers) with the help of the concept and formula of Gravitational Potential, gravitational potential energy, & gravitational force. Also solve: Numericals on Gravitational force and Universal Law of gravitation – class 9 […]

## Resistivity and Conductivity Solved numerical problems (Worked Solutions)

In this post, we have compiled a bunch of interesting numerical problems on Resistivity and Conductivity. These are Solved numerical problems (Worked Solutions). Resistivity and Conductivity numerical problems (solved worksheet) 1 ) Gold has a conductivity of 45 MS m−1. What is the resistance of a 0.01 m diameter gold connector that is 0.05m long? […]

## Specific gravity & Relative Density – are they the same?

A liter of water has a mass of 1.00 kg, but the same volume of methylated spirits has a mass of only 0.79 kg. We can say that the density of methylated spirits is 0.79 that of water. This is called its relative density (RD) or its specific gravity (SG). The two terms ( relative […]

## Heating effect of electric current class 10 – formulas & Numerical

In this post, we will discuss the Heating effect of electric current (class 10) and list down the Heating Effect formulas or Equations of electric power and energy. And, then we will solve a bunch of numerical problems as well using these formulas. Heating effect of current formulas for power and energy The power P […]

## Numerical problems based on the efficiency of machines

In this post, we will first find out what the efficiency of a machine means, and then we will solve numerical problems using the concept and formula of the efficiency of machines. If a machine, such as an electric motor, is used to raise a load, electrical energy must be provided to the motor. This […]

## The force vectors on an aeroplane in steady flight & numerical

In this post, we will study a probable set of force vectors on an aeroplane in steady flight. The forces acting on an aeroplane (airplane) are shown in Figure 1. force vectors on an aeroplane in steady flight Let’s list down the force components acting on the airplane when it’s having a steady flight. The […]

## Numerical problem on Rotational Kinetic Energy

In this post, we will review the formula of Rotational Kinetic Energy and then solve numerical problems based on Rotational Kinetic Energy. Rotational Kinetic Energy formula from the linear kinetic energy formula The equation for linear kinetic energy = KEL = (1/2) m v2 Let’s Convert that equation to its angular analog: KE = (1/2) […]

## Numerical problem on rotational work | Numerical on work done by the torque

In this post, we will find the equation of the work done by Torque. (In other words, we will work with the equation of rotational work.) Then we solve a few numerical problems using this formula of rotational work. Equation of the work done by Torque | equation of rotational work Here we will find […]

## Moments of Inertia – formulas & sample numerical

In this post, we will focus on the formulas of the moment of inertia and also will solve a few interesting sample numerical problems using the moment of inertia formulas. Moments of Inertia – concepts & definition The torque equation gives us: τ =mr2α . This is an important result because it relates to torque […]