{"id":127,"date":"2018-01-15T17:38:34","date_gmt":"2018-01-15T09:38:34","guid":{"rendered":"https:\/\/gurumuda.net\/physics\/?p=127"},"modified":"2018-01-15T17:38:34","modified_gmt":"2018-01-15T09:38:34","slug":"constant-velocity-problems-and-solutions","status":"publish","type":"post","link":"https:\/\/gurumuda.net\/physics\/constant-velocity-problems-and-solutions.htm","title":{"rendered":"Motion with constant velocity \u2013 problems and solutions","gt_translate_keys":[{"key":"rendered","format":"text"}]},"content":{"rendered":"

Solved Problems in Linear Motion<\/a> – Constant velocity<\/a><\/p>\n

1. A car travels at a constant 10 m\/s. Determine distance<\/a> after 10 seconds and 60 seconds.<\/span><\/span><\/p>\n

Solution<\/span><\/span><\/p>\n

Constant speed 10 meters\/second means car travels 10 meters every 1 second. <\/span><\/span><\/p>\n

After 2 seconds, the car travels 20 meters,<\/span><\/span><\/p>\n

After 5 seconds, the car travels 50 meters,<\/span><\/span><\/p>\n

After 10 seconds, the car travels 100 meters<\/u><\/span><\/span>,<\/span><\/span><\/p>\n

After 60 seconds, the car travels 600 meters<\/u><\/span><\/span>.<\/span><\/span><\/p>\n

<\/p>\n

2. A car travels along a straight road at constant 72 km\/h. Determine the car’s distance after 2 minutes and 5 minutes. <\/span><\/span><\/p>\n

Solution<\/span><\/span><\/p>\n

72 km\/h = (72)(1000 meters) \/ 3600 seconds = 72,000 \/ 3600 seconds = 20 meters\/second.<\/span><\/span><\/p>\n

The constant speed at 20 meters\/second means car travels 20 meters every 1 second.<\/span><\/span><\/p>\n

After 120 seconds or 2 minutes, car travels 20 meters x 120 = 2400 meters<\/u><\/span><\/span>,<\/span><\/span><\/p>\n

After 300 seconds or 5 minutes, car travels 20 meters x 300 = 6000 meters<\/u><\/span><\/span>.<\/span><\/span><\/p>\n

<\/p>\n

3. A body travels along a straight road for 100 meters in 50 seconds. Determine the speed of the body.<\/span><\/span><\/p>\n

Solution<\/span><\/span><\/p>\n

100 meters \/ 50 seconds = 10 meters \/ 5 seconds = 2 meters\/second<\/u><\/span><\/span>.<\/span><\/span><\/p>\n

4. Determine speed according to the diagram below….<\/span><\/span><\/p>\n

\"Constant<\/span><\/span>Solution<\/span><\/span><\/p>\n

Speed = Distance \/ time elapsed<\/span><\/span><\/p>\n

Speed = 2 meters \/ 1 second = 4 meters \/ 2 seconds = 6 meters \/ 3 seconds = 8 meters \/ 4 seconds = 2 meters\/second<\/u><\/span><\/span>.<\/span><\/span><\/p>\n

5. <\/span><\/span>Cars A and B approach each other on parallel tracks. When the distance between the two cars is 100 meters, car A moves at a constant speed of 10 m\/s, car B moves at a constant speed of 40 m\/s. Determine (a) the distance of car A before passing car B (b) time interval before car B passing car A.<\/span><\/span><\/span><\/p>\n

Solution<\/span><\/span><\/p>\n

\"ConstantCar A moving with a constant speed at 10 meters\/second, means car A moves as far as 10 meters every 1 second. After 2 seconds, A car move as far as 20 meters.<\/span><\/span><\/span><\/p>\n

Car B moves with a constant speed at 40 meters\/second, means car B moves as far as 40 meters every 1 second. After 2 seconds, car B moves as far as 80 meters.<\/span><\/span><\/span><\/p>\n

20 meters + 80 meters = 100 meters.<\/span><\/span><\/span><\/p>\n

(a) The distance of car A before passing car B is 20 meters. The distance of car B before passing car A is 80 meters.<\/span><\/span><\/span><\/p>\n

(b) Time interval of car B before passing car A is 2 seconds. Time interval of car A before passing car B is 2 seconds<\/span><\/span><\/span><\/p>\n

5. <\/span>If the speedometer <\/span>of a car <\/span>shows 108 km\/h, <\/span>determine the distance traveled by car in one minute.<\/span><\/span><\/span><\/p>\n

Solution :<\/span><\/span><\/p>\n

The speedometer is an instrument to measure speed. The speed of a car is 108 km\/hour.
\n108 km \/ h = (108) (1000 meters) \/ 3600 seconds = 30 meters\/second.<\/span><\/span><\/p>\n

1 minute = 60 seconds<\/span><\/span><\/p>\n

The speed of the car 30 meters\/second means the car moves as far as 30 meters in 1 second.<\/span><\/span><\/p>\n

After 1 second, the car moves as far as 1 x 30 meters = 30 meters.<\/span><\/span><\/p>\n

After 2 seconds, the car moves as far as 2 x 30 meters = 60 meters.<\/span><\/span><\/p>\n

After 60 seconds, the car moves as far as 60 x 30 meters = 1800 meters.<\/span><\/span><\/p>\n

6. <\/span>Tom <\/span>throws <\/span>a <\/span>ball straight <\/span>to Andrew<\/span>. <\/span>Tom and Andrew are <\/span>separated as far as 10.08 m<\/span>eters<\/span>. The ball is thrown <\/span>horizontally <\/span>and moves <\/span>at <\/span>20 m\/<\/span>s <\/span>(ignore gravity). <\/span>Andrew <\/span>hit<\/span>s<\/span> the ball 4.00 x 10<\/span>-3<\/span><\/sup> seconds after the ball was thrown. If the <\/span>hitter <\/span>moves at a constant <\/span>speed <\/span>of 5.00 m\/s, the ball is hit by the <\/span>hitter <\/span>after the <\/span>hitter moves as far as…<\/span><\/span><\/span><\/p>\n

Known :<\/u><\/span><\/span><\/p>\n

The distance between Tom and Andrew = 10.08 meters<\/span><\/span><\/p>\n

Ball’s speed (v) = 20 m\/s<\/span><\/span><\/p>\n

The time interval (t) = 4 x 10-3<\/sup> seconds = 0.004 seconds<\/span><\/span><\/p>\n


\nHitter’s speed (v) = 5 m \/ s<\/span><\/span><\/p>\n


\nWanted:<\/u> The ball is hit by hitter after the ball moves as far as…<\/span><\/span><\/p>\n

Solution :<\/u><\/span><\/span><\/p>\n

Ball’s distance :<\/span><\/span><\/p>\n

s1<\/sub> = v t = (20) (0.004) = 0.08 meters<\/span><\/span><\/p>\n

Hitter’s distance :<\/span><\/span><\/p>\n

s2<\/sub> = v t = 5 t<\/span><\/span><\/p>\n

Ball’s distance + hitter’s distance = distance between Tom and Andrew.<\/span><\/span><\/p>\n

0.08 + 5 t = 10.08<\/span><\/span><\/p>\n

5 t = 10.08 \u2013 0.08<\/span><\/span><\/p>\n

5 t = 10<\/span><\/span><\/p>\n

t = 10\/5<\/span><\/span><\/p>\n

t = 2 seconds<\/span><\/span><\/p>\n


\nHitter’s distance :<\/span><\/span><\/p>\n

s2<\/sub> = v t = 5 t = (5) (2) = 10 meters<\/span><\/span><\/p>\n

7. A hunter with his car is chasing a deer. The car moves at 72 km\/h and the deer run at speeds of 64.8 km\/h. When the distance between the car and the deer is 2012 meters, the hunter fired his shotgun. Bullets out of the gun at 200 m\/s. Determine the time interval of the deer getting shot.<\/span><\/span><\/span><\/p>\n

A. 0.5 s<\/span><\/span><\/p>\n

B. 1 s<\/span><\/span><\/p>\n

C. 1.25 s<\/span><\/span><\/p>\n

D. 1.5 s<\/span><\/span><\/p>\n

Known :<\/u><\/span><\/span><\/p>\n

Speed of car (v<\/span><\/span>b<\/span><\/sub>) = 72 km\/h = (72)(1000 m) \/ 3600 s = 20 m\/s <\/span><\/span><\/p>\n

Speed of deer (v<\/span><\/span>r<\/span><\/sub>) = 64.8 km\/h = (64.8)(1000 m) \/ 3600 s = 64800 m \/ 3600 s = 18 m\/s <\/span><\/span><\/p>\n

When the bullet is fired, the distance between the car and the deer <\/span><\/span><\/span>(s) = 202 meters<\/span><\/span><\/p>\n

Speed of fire (v<\/span><\/span>p<\/span><\/sub>) = 20 m\/s + 200 m\/s = 220 m\/s<\/span><\/span><\/p>\n

Weapons held by hunters who are in a car that moves with a speed of 20 m\/s so that the speed of car is also added to the speed of the bullet.<\/span><\/span><\/span><\/p>\n

Wanted:<\/u><\/span><\/span> Determine the time interval of the deer getting shot<\/span><\/span><\/span><\/p>\n

Solution :<\/u><\/span><\/span><\/p>\n

Think of cars and deer moving at a constant velocity.<\/span><\/span><\/span><\/p>\n

Equation : v = s \/ t or s = v t<\/span><\/span><\/p>\n

v = speed, s = distance, t = time interval<\/i><\/span><\/span><\/p>\n

Distance = 202 + X<\/span><\/span>r<\/span><\/sub> = 202 + v<\/span><\/span>r<\/span><\/sub> t = 202 + 18 t<\/span><\/span><\/p>\n

Distance = Y<\/span><\/span>p<\/span><\/sub> = v<\/span><\/span>p<\/span><\/sub> t = 220 t<\/span><\/span><\/p>\n

Distance traveled by deer = distance traveled by bullet<\/span><\/span><\/p>\n

202 + 18 t = 220 t<\/span><\/span><\/p>\n

202 = 220 t \u2013 18 t<\/span><\/span><\/p>\n

202 = 202 t<\/span><\/span><\/p>\n

t = 202\/202 <\/span><\/span><\/p>\n

t = 1 second<\/span><\/span><\/p>\n

The correct answer is B.<\/span><\/span><\/p>\n

<\/p>\n

[wpdm_package id=’507′]<\/p>\n

[wpdm_package id=’517′]<\/p>\n

    \n
  1. Distance and displacement<\/a><\/li>\n
  2. Average speed and average velocity<\/a><\/li>\n
  3. Constant velocity<\/a><\/li>\n
  4. Constant acceleration<\/a><\/li>\n
  5. Free fall motion<\/a><\/li>\n
  6. Down motion in free fall<\/a><\/li>\n
  7. Up and down motion in free fall<\/a><\/li>\n<\/ol>\n

    <\/p>\n","protected":false,"gt_translate_keys":[{"key":"rendered","format":"html"}]},"excerpt":{"rendered":"

    Solved Problems in Linear Motion – Constant velocity 1. A car travels at a constant 10 m\/s. Determine distance after 10 seconds and 60 seconds. Solution Constant speed 10 meters\/second means car travels 10 meters every 1 second. After 2 seconds, the car travels 20 meters, After 5 seconds, the car travels 50 meters, After … Read more<\/a><\/p>\n","protected":false,"gt_translate_keys":[{"key":"rendered","format":"html"}]},"author":1,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_seopress_titles_title":"","_seopress_titles_desc":"","_seopress_robots_index":"","_seopress_robots_follow":"","_seopress_robots_imageindex":"","_seopress_robots_snippet":"","_seopress_robots_primary_cat":"","_seopress_robots_breadcrumbs":"","_seopress_robots_freeze_modified_date":"","_seopress_robots_custom_modified_date":"","_seopress_robots_canonical":"","_seopress_social_fb_title":"","_seopress_social_fb_desc":"","_seopress_social_fb_img":"","_seopress_social_fb_img_attachment_id":0,"_seopress_social_fb_img_width":0,"_seopress_social_fb_img_height":0,"_seopress_social_twitter_title":"","_seopress_social_twitter_desc":"","_seopress_social_twitter_img":"","_seopress_social_twitter_img_attachment_id":0,"_seopress_social_twitter_img_width":0,"_seopress_social_twitter_img_height":0,"_seopress_redirections_value":"","_seopress_redirections_enabled":"","_seopress_redirections_enabled_regex":"","_seopress_redirections_logged_status":"","_seopress_redirections_param":"","_seopress_redirections_type":0,"_seopress_analysis_target_kw":"Motion with constant velocity \u2013 problems and solutions","_seopress_news_disabled":"","_seopress_video_disabled":"","_seopress_video":[],"_seopress_pro_schemas_manual":[],"_seopress_pro_rich_snippets_disable_all":"","_seopress_pro_rich_snippets_disable":[],"_seopress_pro_schemas":[],"footnotes":""},"categories":[3],"tags":[],"class_list":["post-127","post","type-post","status-publish","format-standard","hentry","category-solved-problems-in-basic-physics"],"gt_translate_keys":[{"key":"link","format":"url"}],"_links":{"self":[{"href":"https:\/\/gurumuda.net\/physics\/wp-json\/wp\/v2\/posts\/127","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/gurumuda.net\/physics\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/gurumuda.net\/physics\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/gurumuda.net\/physics\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/gurumuda.net\/physics\/wp-json\/wp\/v2\/comments?post=127"}],"version-history":[{"count":0,"href":"https:\/\/gurumuda.net\/physics\/wp-json\/wp\/v2\/posts\/127\/revisions"}],"wp:attachment":[{"href":"https:\/\/gurumuda.net\/physics\/wp-json\/wp\/v2\/media?parent=127"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/gurumuda.net\/physics\/wp-json\/wp\/v2\/categories?post=127"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/gurumuda.net\/physics\/wp-json\/wp\/v2\/tags?post=127"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}