{"id":199319,"date":"2025-03-11T15:00:07","date_gmt":"2025-03-11T15:00:07","guid":{"rendered":"https:\/\/learnexams.com\/blog\/?p=199319"},"modified":"2025-03-11T15:00:09","modified_gmt":"2025-03-11T15:00:09","slug":"a-car-starts-from-rest-and-accelerates-at-a-constant-1-5-m-s2-2","status":"publish","type":"post","link":"https:\/\/www.learnexams.com\/blog\/2025\/03\/11\/a-car-starts-from-rest-and-accelerates-at-a-constant-1-5-m-s2-2\/","title":{"rendered":"A car starts from rest and accelerates at a constant 1.5 m\/s2"},"content":{"rendered":"\n

A car starts from rest and accelerates at a constant 1.5 m\/s2. Some time later, it takes 2.1 s to cross over a 25-meter long bridge. How far did the car travel before getting onto the bridge?<\/p>\n\n\n\n

The correct answer and explanation is :<\/strong><\/mark><\/p>\n\n\n\n

The car traveled approximately 35.57 meters<\/strong> before getting onto the bridge.<\/p>\n\n\n\n

Explanation:<\/h3>\n\n\n\n
    \n
  1. Understanding the problem<\/strong>:<\/li>\n<\/ol>\n\n\n\n
      \n
    • The car starts from rest and accelerates at (1.5 \\, \\text{m\/s}^2).<\/li>\n\n\n\n
    • It takes 2.1 seconds<\/strong> to cross a 25-meter bridge<\/strong>.<\/li>\n\n\n\n
    • We need to determine how far the car traveled before reaching the bridge.<\/li>\n<\/ul>\n\n\n\n
        \n
      1. Finding the velocity at the start of the bridge<\/strong>:<\/li>\n<\/ol>\n\n\n\n
          \n
        • Using the equation for distance under constant acceleration:
          [
          s = v t + \\frac{1}{2} a t^2
          ]<\/li>\n\n\n\n
        • Plugging in values:
          [
          25 = v \\cdot 2.1 + \\frac{1}{2} \\times 1.5 \\times (2.1)^2
          ]<\/li>\n\n\n\n
        • Solving for ( v ), we get:
          [
          v = 8.81 \\text{ m\/s}
          ]<\/li>\n<\/ul>\n\n\n\n
            \n
          1. Finding the time taken to reach this velocity<\/strong>:<\/li>\n<\/ol>\n\n\n\n
              \n
            • Using the equation of motion:
              [
              v = u + at
              ]<\/li>\n\n\n\n
            • Since ( u = 0 ), solving for ( t ):
              [
              8.81 = 1.5 t
              ]
              [
              t = 5.87 \\text{ seconds}
              ]<\/li>\n<\/ul>\n\n\n\n
                \n
              1. Finding the distance traveled before the bridge<\/strong>:<\/li>\n<\/ol>\n\n\n\n
                  \n
                • Using the equation:
                  [
                  s = ut + \\frac{1}{2} a t^2
                  ]<\/li>\n\n\n\n
                • Since ( u = 0 ), solving for ( s ):
                  [
                  s = \\frac{1}{2} \\times 1.5 \\times (5.87)^2
                  ]
                  [
                  s \\approx 35.57 \\text{ meters}
                  ]<\/li>\n<\/ul>\n\n\n\n

                  Thus, the car traveled 35.57 meters<\/strong> before reaching the bridge. <\/p>\n","protected":false},"excerpt":{"rendered":"

                  A car starts from rest and accelerates at a constant 1.5 m\/s2. Some time later, it takes 2.1 s to cross over a 25-meter long bridge. How far did the car travel before getting onto the bridge? The correct answer and explanation is : The car traveled approximately 35.57 meters before getting onto the bridge. […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","ast-disable-related-posts":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"footnotes":""},"categories":[25],"tags":[],"class_list":["post-199319","post","type-post","status-publish","format-standard","hentry","category-exams-certification"],"_links":{"self":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/199319","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/comments?post=199319"}],"version-history":[{"count":0,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/199319\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/media?parent=199319"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/categories?post=199319"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/tags?post=199319"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}