At what height over the earth's pole, the free fall acceleration decreases by one percent \(=\ldots \ldots \ldots \mathrm{km}(\mathrm{Re}=6400 \mathrm{~km})\) (A) 32 (B) 80 (C) \(1.253\) (D) 64

Short Answer

Expert verified
The height above the Earth's pole where the free fall acceleration decreases by one percent is approximately \(64~km\). Therefore, the correct answer is (D) 64.

Step by step solution

01

Write down the formula for acceleration due to gravity

The formula for acceleration due to gravity is given by: \(g = \frac{GM}{(R+h)^2}\) where \(g\) is the acceleration due to gravity at height \(h\), \(G\) is the gravitational constant, \(M\) is the mass of Earth, and \(R\) is the radius of Earth.
02

Determine the acceleration due to gravity at the Earth's surface

At the Earth's surface, the height \(h\) is equal to 0. So the acceleration due to gravity at the Earth's surface, \(g_0\), is given by: \(g_0 = \frac{GM}{R^2}\)
03

Calculate the acceleration due to gravity at one percent less than the surface acceleration

We are given that we need to find the height where the acceleration due to gravity has decreased by one percent of the surface acceleration (\(g_0\)). So we need to calculate \(g_1\), which is given by: \(g_1 = g_0 - (0.01 \times g_0)\)
04

Set up an equation for the height at which the acceleration due to gravity is one percent less than the surface acceleration

We can now set up an equation to solve for the height (\(h\)) when \(g = g_1\). This equation can be written as: \(\frac{GM}{(R+h)^2} = g_1\)
05

Substitute \(g_0\) in terms of \(R\) and \(M\) into the equation for one percent less acceleration

Substituting \(g_0 = \frac{GM}{R^2}\) into our equation, we get: \(\frac{GM}{(R+h)^2} = \frac{GM}{R^2} - \frac{GM}{100 R^2}\)
06

Solve for the height (\(h\))

Now, we can rearrange the equation to solve for the height (\(h\)): \(h = \sqrt{\frac{GM}{\frac{99 GM}{100R^2}}} - R\)
07

Substitute the radius of Earth (\(R\)) and simplify the equation

We are given the radius of Earth (\(R=6400\) km) and can substitute this into our equation to get: \(h = \sqrt{\frac{GM}{\frac{99 GM}{(6400 \times 10^3)^2}}} - 6400 \times 10^3\) Notice that the \(GM\) terms cancel each other out, and we are left with: \(h = \sqrt{\frac{100}{99} \times (6400 \times 10^3)^2} - 6400 \times 10^3\)
08

Calculate the height (\(h\))

Now, we can calculate the height (\(h\)) using the above equation: \(h \approx 64000~m\)
09

Convert the height to kilometers and make a comparison with answer options

Converting the height to kilometers, we get: \(h \approx 64~km\) Looking at the answer options, we can see that the closest answer to our solution is (D) 64 km.

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Over 30 million students worldwide already upgrade their learning with Vaia!

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

Direction (Read the following questions and choose) (A) If both Assertion and Reason are true and the Reason is correct explanation of assertion (B) If both Assertion and Reason are true, but reason is not correct explanation of the Assertion (C) If Assertion is true, but the Reason is false (D) If Assertion is false, but the Reason is true Assertion: The square of the period of revolution of a planet is proportional to the cube of its distance from the sun. Reason: Sun's gravitational field is inversely proportional to the square of its distance from the planet (a) \(\mathrm{A}\) (b) \(\mathrm{B}\) (c) \(\mathrm{C}\) (d) D

Density of the earth is doubled keeping its radius constant then acceleration, due to gravity will be \(-m s^{-2}\) \(\left(\mathrm{g}=9.8 \mathrm{~ms}^{2}\right)\) (A) \(19.6\) (B) \(9.8\) (C) \(4.9\) (D) \(2.45\)

Energy required to move a body of mass \(\mathrm{m}\) from from an orbit of radius \(2 \mathrm{R}\) to \(3 \mathrm{R}\) is \(\ldots \ldots \ldots \ldots\) (A) \(\left[(\mathrm{GMm}) /\left(12 \mathrm{R}^{2}\right)\right]\) (B) \(\left[(\mathrm{GMm}) /\left(3 \mathrm{R}^{2}\right)\right]\) (C) \([(\mathrm{GMm}) /(8 \mathrm{R})]\) (D) \([(\mathrm{GMm}) /(6 \mathrm{R})]\)

3 particle each of mass \(\mathrm{m}\) are kept at vertices of an equilateral triangle of side \(L\). The gravitational field at center due to these particles is (A) zero (B) \(\left[(3 \mathrm{GM}) / \mathrm{L}^{2}\right]\) (C) \(\left[(9 \mathrm{GM}) / \mathrm{L}^{2}\right]\) (D) \((12 / \sqrt{3})\left(\mathrm{Gm} / \mathrm{L}^{2}\right)\)

The escape velocity of a body from earth's surface is Ve. The escape velocity of the same body from a height equal to 7 R from earth's surface will be (A) \((\mathrm{Ve} / \sqrt{2})\) (B) \((\mathrm{Ve} / 2)\) (C) \((\mathrm{Ve} / 2 \sqrt{2})\) (D) \((\mathrm{Ve} / 4)\)

See all solutions

Recommended explanations on English Textbooks

View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.

Sign-up for free