A radioactive substance decays to 1/16th of its original mass in 20 days. Half-life is MCQ with Answer and Explanation
Question
Report Error
Discuss this Question (0)
Practice More Physics Questions
Question #1
Report Error
The phenomenon of mirage is due to
Correct Answer: Option D
Explanation:
Mirage occurs due to refraction of light through air layers of different temperatures (densities) and total internal reflection when ray tries to go from denser to rarer medium at grazing incidence. It's an optical illusion, not real water.
Mirage occurs due to refraction of light through air layers of different temperatures (densities) and total internal reflection when ray tries to go from denser to rarer medium at grazing incidence. It's an optical illusion, not real water.
Question #2
Report Error
The half-life of a radioactive substance is 10 days. After 30 days, the fraction decayed is
Question #3
Report Error
If a stone is tied to a string and whirled in a circle, and the string suddenly breaks, the stone will:
Correct Answer: Option A
Explanation:
When the stone is moving in a circle, its velocity vector is always tangential to the circle. The string provides the necessary centripetal force directed towards the center. When the string breaks, this inward force ceases to exist. Due to inertia of direction (Newton's First Law), the stone continues to move along the tangent at the point where the string broke.
When the stone is moving in a circle, its velocity vector is always tangential to the circle. The string provides the necessary centripetal force directed towards the center. When the string breaks, this inward force ceases to exist. Due to inertia of direction (Newton's First Law), the stone continues to move along the tangent at the point where the string broke.
No comments yet. Be the first to start the discussion!