Question
A thief snatched a lady's purse and began running north
towards a bus that was 200 meters away. A policeman, who was standing 40 meters south of the lady, noticed this and immediately sent his dog after the thief. The dog caught the thief 2 seconds before reaching the bus. If the dog's speed was 25 m/s, determine the speed of the thief.Solution
Let the speed of the thief be 'x' m/s. Time required by the thief to catch the bus = (200/x) seconds Time taken by the dog to catch the thief = {(200/x) - 2} seconds ATQ; {40/(25 - x)} = {(200/x) - 2} Or, 40x = (200 - 2x) X (25 - x) Or, 20x = (100 - x) X (25 - x) Or, 20x = 2500 - 100x - 25x + x2 Or, x2Â - 145x + 2500 = 0 Or, x2Â - 125x - 20x + 2500 = 0 Or, x(x - 125) - 20(x - 125) = 0 Or, (x - 125)(x - 20) = 0 So, x = 125 or x = 20 But since the speed of the thief cannot be more than the speed of the dog So, x = 20.
Which of these device is used to provide internet to a network?
Which wireless standard provides the fastest data transfer rates in a Wi-Fi network?
POST stands for ..................
Which of the following is the function of an IP address?
Which layer of the OSI model is used for providing a means for two applications to communicate with each other?
Which of the following is not type of internet connection?
...................... is the creation of email messages with a forged sender address - something which is simple to do because the core protocols do no...
________ is a secure electronic "tunnel" through the Internet that prevents unauthorized access or eavesdropping.
Which of the following is the slowest Internet connection?
The process of transferring files from computer on the internet is called: