B) How fast should a boy of 40kg mass run so that the kinetic energy becomes 800J?

v = 6.32  m/s

Step-by-step explanation:

Given Data:

Mass = m = 40 kg

Kinetic Energy = KE = 800 J

Required:

Speed = v = ?

Formula:

Solution:

Rearrange the formula for speed

Hope this helped!

e^-kt = n/n0 = 0.79  

-kt = ln 0.79  

t = - ln 0.79/0.0001  

= 2357 years

step-by-step explanation:

explanation:

infrared radiation has wavelength in the range between 700 nm and 1 mm. lets' convert these values into scientific notation, keeping in mind that:

let's start from the lower value, we have:

(we moved the dot two places to the left, so we increased the exponent by 2 units, from -9 to -7)

the higher value is:

so, the range of wavelength of infrared radiation is: