Kinematics and Dynamics Kinematics and Dynamics Physics Help Forum

 Aug 22nd 2014, 01:15 AM #1 Junior Member   Join Date: Aug 2014 Posts: 3 Please help me to find these answers, my exam is near. Hi everyone!I m new member to this forum, I hope it's really useful site..My exam are near and I tried my best to answers these questions but couldn't.I have many questions among them posting 1..will post other..please answer me. 1.Rain drops hitting the side windows of a car in motion often leave diagonal streaks.why?
 Aug 22nd 2014, 04:43 AM #2 Senior Member     Join Date: Apr 2008 Location: Bedford, England Posts: 668 Vector Addition Think first what would happen in a stationary car (on a windless day) The rain drops are coming straight down, relative to the car window, so the streak on the window will be straight down. Now consider what happens if the car (and thus the window) is moving. The motion of the raindrop relative to the window is no longer straight down. Imagine an observer standing at a buss stop (for example). The observer sees the rain coming straight down and the car moving horizontally The motion of the raindrop relative to the window is given by adding the straight down motion of the raindrop to the horizontal motion of the car giving a diagonal motion.
Aug 22nd 2014, 05:25 PM   #3
Junior Member

Join Date: Aug 2014
Posts: 3
 Originally Posted by MBW Think first what would happen in a stationary car (on a windless day) The rain drops are coming straight down, relative to the car window, so the streak on the window will be straight down. Now consider what happens if the car (and thus the window) is moving. The motion of the raindrop relative to the window is no longer straight down. Imagine an observer standing at a buss stop (for example). The observer sees the rain coming straight down and the car moving horizontally The motion of the raindrop relative to the window is given by adding the straight down motion of the raindrop to the horizontal motion of the car giving a diagonal motion.

thank u so much..

 Aug 22nd 2014, 05:26 PM #4 Junior Member   Join Date: Aug 2014 Posts: 3 Can we have zero accerlation but non zero velocity?
Aug 23rd 2014, 05:37 PM   #5
Physics Team

Join Date: Jun 2010
Location: Morristown, NJ USA
Posts: 2,333
 Originally Posted by binod Can we have zero accerlation but non zero velocity?
Of course. A car coasting along a road may have zero acceleration and velocity of 60 MPH.

,

,

,

,

,

,

,

,

,

,

,

,

,

,

# raindrops hitting the side windows of a car in motion often leave diagonal streaks. Why

Click on a term to search for related topics.
 Thread Tools Display Modes Linear Mode

 Similar Physics Forum Discussions Thread Thread Starter Forum Replies Last Post berniecooke Kinematics and Dynamics 2 Mar 9th 2015 08:21 AM shoushanik Kinematics and Dynamics 3 Aug 8th 2014 07:05 AM honestliar Kinematics and Dynamics 1 Oct 26th 2009 10:10 PM