/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Problem 9 You drop a rock from a cliff. If... [FREE SOLUTION] | 91Ó°ÊÓ

91Ó°ÊÓ

You drop a rock from a cliff. If air resistance is neglected, which of the following statements is (are) true? 1\. The speed of the rock will increase. 2\. The speed of the rock will decrease. 3\. The acceleration of the rock will increase. 4\. The acceleration of the rock will decrease. a) 1 b) 1 and 4 c) 2 d) 2 and 3

Short Answer

Expert verified
a) The speed of the rock will increase. b) The speed of the rock will decrease. c) The acceleration of the rock will increase. d) The acceleration of the rock will decrease. Answer: a) The speed of the rock will increase.

Step by step solution

01

Understand the motion of the rock in free fall

When a rock is dropped from a cliff, it is in free fall. In the absence of air resistance, the only force acting on the rock is gravity, which pulls the rock downward. The acceleration due to gravity (g) is constant (approximately 9.81 m/s^2).
02

Analyze statement 1

Statement 1 says that the speed of the rock will increase. As the rock is in free fall, it will accelerate downwards due to gravity. This means that its speed will increase in the downward direction. So, statement 1 is true.
03

Analyze statement 2

Statement 2 says that the speed of the rock will decrease. We have already determined in step 2 that the speed of the rock will increase, so statement 2 is false.
04

Analyze statement 3

Statement 3 says that the acceleration of the rock will increase. However, we know that the acceleration of the rock in free fall is constant (approximately 9.81 m/s^2) due to gravity. So, the acceleration does not increase. Hence, statement 3 is false.
05

Analyze statement 4

Statement 4 says that the acceleration of the rock will decrease. As we established in step 4, the acceleration of an object in free fall is constant (approximately 9.81 m/s^2). So, the acceleration does not decrease either. Statement 4 is false.
06

Conclude the correct answer

Looking at the given options, the correct answer is: a) 1 - Only statement 1 is true as it states that the speed of the rock will increase due to the constant acceleration caused by gravity.

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 91Ó°ÊÓ!

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

An electron, starting from rest and moving with a constant acceleration, travels \(1.0 \mathrm{~cm}\) in \(2.0 \mathrm{~ms}\). What is the magnitude of this acceleration? a) \(25 \mathrm{~km} / \mathrm{s}^{2}\) b) \(20 \mathrm{~km} / \mathrm{s}^{2}\) c) \(15 \mathrm{~km} / \mathrm{s}^{2}\) d) \(10 \mathrm{~km} / \mathrm{s}^{2}\) e) \(5.0 \mathrm{~km} / \mathrm{s}^{2}\)

A girl is riding her bicycle. When she gets to a corner, she stops to get a drink from her water bottle. At that time, a friend passes by her, traveling at a constant speed of \(8.0 \mathrm{~m} / \mathrm{s}\). a) After \(20 \mathrm{~s}\), the girl gets back on her bike and travels with a constant acceleration of \(2.2 \mathrm{~m} / \mathrm{s}^{2} .\) How long does it take for her to catch up with her friend? b) If the girl had been on her bike and rolling along at a speed of \(1.2 \mathrm{~m} / \mathrm{s}\) when her friend passed, what constant acceleration would she need to catch up with her friend in the same amount of time?

A ball is dropped from the roof of a building. It hits the ground and it is caught at its original height 5.0 s later. a) What was the speed of the ball just before it hits the ground? b) How tall was the building? c) You are watching from a window \(2.5 \mathrm{~m}\) above the ground. The window opening is \(1.2 \mathrm{~m}\) from the top to the bottom. At what time after the ball was dropped did you first see the ball in the window?

The Bellagio Hotel in Las Vegas, Nevada, is well known for its Musical Fountains, which use 192 HyperShooters to fire water hundreds of feet into the air to the rhythm of music. One of the HyperShooters fires water straight upward to a height of \(240 \mathrm{ft}\). a) What is the initial speed of the water? b) What is the speed of the water when it is at half this height on its way down? c) How long will it take for the water to fall back to its original height from half its maximum height?

Starting from rest, a boat increases its speed to \(5.00 \mathrm{~m} / \mathrm{s}\) with constant acceleration. a) What is the boat's average speed? b) If it takes the boat 4.00 s to reach this speed, how far has it traveled?

See all solutions

Recommended explanations on Physics 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.