Log out Go to App
Go to App

Learning Materials

Features

Discover

Chapter 3: Q21. (page 67)

If you stand motionless under an umbrella in a rainstorm where the drops fall vertically, you remain relatively dry. However, if you start running, the rain begins to hit your legs even if they remain under the umbrella. Why?

Short Answer

Expert verified

If you start running, the rain will hit your legs because of its horizontal component of velocity.

Step by step solution

01

Step 1. Motionless in a rainstorm

In a rainstorm, if a person is standing still in a cylindrical shape in which there is no rain, the horizontal component of the rain is zero, and rain cannot move from outside the cylinder.

Sometimes the rain hits the legs even if a person is standing still in a rainstorm because, in this situation, the rain will have some horizontal component of velocity towards the person.

02

Step 2. Determine why the rain hits your legs while you are running

When any person is standing under an umbrella, they remain dry, but if the person is running with an umbrella, they are moving with a forward horizontal velocity. The rain will have a backward horizontal velocity relative to the person. So, the rain begins to hit your legs even if they remain under the umbrella.

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.

Start your free trial

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

Which of the following statements are not valid for a projectile? Take the upward direction as positive.

(a) The projectile has the same x velocity at any point on its path.

(b) The acceleration of the projectile is positive and decreasing when the projectile is moving upward, zero at the top, and increasingly negative as the projectile descends.

(c) The acceleration of the projectile is a constant negative value.

(d) The y component of the velocity of the projectile is zero at the highest point of the projectile’s path.

(e) The velocity at the highest point is zero.

An airplane is heading due south at a speed of 688 km/h. If a wind begins blowing from the southwest at a speed of 90.0 km/h (average), calculate (a) the velocity (magnitude and direction) of the plane relative to the ground and (b) how far from its intended position it will be after 11.0 min if the pilot takes no corrective action. [Hint: First, draw a diagram.]

Suppose the rescue plane of Problem 31 releases the supplies a horizontal distance of 425 m in advance of the mountain climbers. What vertical velocity (up or down) should the supplies be given so that they arrive precisely at the climbers’ position (Fig. 3–39)? With what speed do the supplies land?

FIGURE 3-39Problem 32

A car moving at 95 km/h passes a 1.00-km-long train traveling in the same direction on a track that is parallel to the road. If the speed of the train is 75 km/h, how long does it take the car to pass the train, and how far will the car have travelled in this time? What are the results if the car and train are instead traveling in opposite directions?

A person in the passenger basket of a hot-air balloon throws a ball horizontally outward from the basket with a speed of 10.0 m/s (Fig. 3–44). What initial velocity (magnitude and direction) does the ball have relative to a person standing on the ground (a) if the hot-air balloon is rising at 3.0 m/s relative to the ground during this throw, and (b) if the hot-air balloon is descending at 3.0 m/s relative to the ground?

FIGURE 3-44 Problem 43
See all solutions

Recommended explanations on Physics Textbooks

Fundamentals of Physics

Read Explanation

Linear Momentum

Read Explanation

Nuclear Physics

Read Explanation

Solid State Physics

Read Explanation

Physical Quantities And Units

Read Explanation

Force

Read Explanation
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