Explanation

In uniform circular motion, instantaneous velocity is tangent to the circular path.

Instantaneous acceleration (centripetal) is directed toward the center, making the two vectors perpendicular to each other.

Explanation

An ammeter is always connected in series with a circuit to measure the current. 

In a series circuit, the current flows through each component one after the other, meaning the same current passes through every device in the circuit.

Since an ammeter is designed to measure the current flowing through a circuit, placing it in series ensures that the entire current passes through it. 

Explanation

The correct equation representing Heisenberg's uncertainty principle is A) Δx. Δp ≥ ħ/2. 

This equation relates the uncertainty in position (Δx) to the uncertainty in momentum (Δp),

Where "ħ" is the reduced Planck constant. 

Explanation

The formula for Newton's Second Law of Motion is:

$$F = ma$$

Where:

• $F$ = Force (in Newtons, N)

• $m$ = Mass of the object (in kilograms, kg)

• $a$ = Acceleration of the object (in meters per second squared, m/s²)

Explanation

The total discount is not simply added. Use the formula:
Effective discount =$a + b - frac{ab}{100}$

$10 + 15 - frac{10 times 15}{100} = 25 - 1.5 = 23.5$

Explanation

An electric kettle converts electrical energy into heat energy using a heating element, usually made of metal.

This heat energy is then used to boil water or heat other liquids.

The process is an example of the conversion of electrical energy into thermal energy.

Explanation

Energy of one photon (E) = hc / λ

h = 6.626 × 10^-34 Js

c = 3 × 10^8 m/s

λ = 4961 Å = 4961 × 10^-10 m

E = (6.626 × 10^-34 Js × 3 × 10^8 m/s) / (4961 × 10^-10 m)

= 4.007 × 10^-19 J

Number of photons required to do 1 J of work:

n = 1 J / (4.007 × 10^-19 J)

= 2.4961 × 10^18

Explanation

The sun is visible a little before it rises and a little after it sets because of atmospheric refraction.

Refraction is the phenomenon that occurs when light changes direction as it passes from one transparent medium to another.

Explanation

UJT (Uni-Junction Transistor) is also known as Double Base.

It has two bases and one emitter, distinguishing it from other transistors.

Explanation

Before measuring with an oscilloscope, it must be calibrated:

Voltage wise: For accurate voltage readings.

Time wise: For precise timing and frequency.

Frequency wise: For correct frequency measurement.

Wave shape wise: To ensure accurate waveform display.