Home » General Knowledge » Physics

Friction and walking: Sand vs. concrete. Why is it more difficult to walk on a sandy surface than on a rigid concrete road under the same conditions? Choose the correct option.

Difficulty: Easy

Sand yields, reducing normal reaction and friction
Concrete has lower coefficient of friction
Air resistance is higher near sand
Shoes become heavier on concrete

Correct Answer: Sand yields, reducing normal reaction and friction

Explanation:

Concept

Static friction ∝ normal reaction × coefficient of friction.
On sand, the surface deforms and shifts, reducing effective normal reaction and reliable contact, so available friction is less.

Final Answer
Sand yields, reducing normal reaction and friction

← Previous Question Next Question→

More Questions from Physics

Nuclear scales: Unit for nuclear sizes. In nuclear physics, typical nuclear radii are expressed using which specialized unit? Choose the correct option.
Boiling point under different locations: Pressure cooker with valve open. Of the locations listed in the options, a pressure cooker operated with the pressure valve open will attain its highest inside temperature at which location? Choose the correct option.
Nobel Prize in Physics (1930): C. V. Raman’s discovery. Sir C. V. Raman received the Nobel Prize for his work on which radiation-related phenomenon, involving inelastic scattering and wavelength shift? Choose the correct option.
Stellar astronomy: Stars that appear single but are double in a telescope. What are stars called that look single to the naked eye yet resolve into two components when viewed through a telescope? Choose the correct option.
Radioactivity: Which emission is not characteristic of ordinary radioactive decay? From the types listed, identify the one not typically emitted in standard (natural) radioactive decay chains. Choose the correct option.
Vector vs. scalar: Identify the vector quantity. Which of the following physical quantities has both magnitude and direction (i.e., is a vector)? Choose the correct option.
Everyday capillarity: Why oil rises in a lamp wick. Oil rises up a lamp’s cotton wick primarily due to which physical principle in fine capillaries? Choose the correct option.
Energy units: Convert watt-hour to joules. One watt-hour represents the energy expended by 1 watt sustained for 1 hour. What is this energy in joules? Choose the correct option.
Dimensional analysis MCQ: Identify the pair of physical quantities that do not share identical dimensions. Out of the following pairs, determine which pair has different dimensional formula; assume standard M–L–T system for mechanics quantities. Choose the correct option.
Applications of radioisotopes: What does the radiocarbon (C-14) dating technique estimate? Choose the most appropriate target material that C-14 dating is designed to age-date in archaeology and geology. Choose the correct option.

Discussion & Comments

No comments yet. Be the first to comment!

Join Discussion