The speed of a falling object is directly proportional to the time for which it falls. The speed after 5 seconds is 49 metres/seconds. What is the speed of an object which falls for 8 seconds?

x/8 = 49/5

To solve this problem, we can use a proportionality relationship between speed and time. Let's set up an equation using the information given:

Speed = constant * time

We're told that the speed after 5 seconds is 49 meters/second. Let's use this information to find the constant:

49 = constant * 5

To find the constant, we divide both sides of the equation by 5:

constant = 49 / 5

constant = 9.8

Now that we have the constant, we can determine the speed of an object that falls for 8 seconds using the equation:

Speed = constant * time

Speed = 9.8 * 8

Speed = 78.4 meters/second

Therefore, the speed of an object that falls for 8 seconds is 78.4 meters/second.

To solve this problem, we can use the given information and set up a proportion between time and speed.

We are told that the speed of a falling object is directly proportional to the time for which it falls. This can be written as:

Speed ∝ Time

Now, let's use the given information to find the constant of proportionality. We know that when the object falls for 5 seconds, the speed is 49 meters/second. Therefore, we can write:

Speed = k * Time

Where "k" is the constant of proportionality. Plugging in the values we have:

49 = k * 5

To find the value of "k," we divide both sides of the equation by 5:

k = 49 / 5
k = 9.8

Now that we have the value of "k," we can use it to find the speed of the object when it falls for 8 seconds. Using the equation we derived earlier:

Speed = k * Time

Plugging in the values:

Speed = 9.8 * 8
Speed = 78.4 meters/second

Therefore, the speed of the object after falling for 8 seconds is 78.4 meters/second.