BCA STEM Concepts 2

Question 1

A wave traveling in a medium has a frequency of 440 Hz and a wavelength of 0.75 m. What is its wave speed?

Accepted Answer

330 m/s

Answer

Wave speed = frequency × wavelength = 440 × 0.75 = 330 m/s.

Question 2

In a chemical reaction, if the activation energy is lowered by a catalyst, what happens to the reaction rate?

Accepted Answer

It increases

Answer

A catalyst lowers activation energy, allowing more molecules to overcome the energy barrier and increasing the reaction rate.

Question 3

Which data structure operates on a Last-In, First-Out (LIFO) principle?

Accepted Answer

Stack

Answer

A stack is a LIFO structure where the most recently added element is the first to be removed.

Question 4

The Pythagorean theorem states that in a right triangle with legs a and b and hypotenuse c, which equation holds?

Accepted Answer

a² + b² = c²

Answer

The Pythagorean theorem is a² + b² = c², relating the squares of the legs to the square of the hypotenuse.

Question 5

What is the primary function of mitochondria in a eukaryotic cell?

Accepted Answer

Produce ATP through cellular respiration

Answer

Mitochondria generate ATP via oxidative phosphorylation, earning the title 'powerhouse of the cell.'

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