/*! 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} Q. 81 A projectile fired into the firs... [FREE SOLUTION] | 91Ó°ÊÓ

91Ó°ÊÓ

A projectile fired into the first quadrant from

the origin of a coordinate system will pass through the point

(x, y) at time t according to the relationship cotθ=2x2y+gt2,

where θ= the angle of elevation of the launcher and g =

the acceleration due to gravity = 32.2ft/sec2

. An artilleryman is firing at an enemy bunker located 2450 feet

up the side of a hill that is 6175 feet away. He fires a round,

and exactly 2.27 seconds later he scores a direct hit.

(a) What angle of elevation did he use?

(b) If the angle of elevation is also given by secθ=v0tx

x , wherev0is the muzzle velocity of the weapon, find the muzzle

velocity of the artillery piece he used.

Short Answer

Expert verified

(a) The angle of elevation is 22.3∘.

(b) The muzzle velocity is2940.20ft/sec.

Step by step solution

01

Part (a) Step 1. Given Information

An artilleryman is firing at an enemy bunker located 2450 feet

up the side of a hill that is 6175 feet away. He fires a round,

and exactly 2.27 seconds later he scores a direct hit.


02

Part (a) Step 2. Calculation

hill=6175ftenemy=2450ftcotθ=2(6175)2(2450)+(32.2)(2.27)=123505065.92338=2.4379therefore,θ=cot-12.4379=22.3∘

03

Part (b) Step 1. Calculation

Substitutex,tandθintheequationsec22.3=v0(2.27)6175=0.0003676v0sec22.30.0003676=0.0003659v00.0003676v0=sec22.30.0003676=1.08080.0003676=2940.23

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

Study anywhere. Anytime. Across all devices.