If a 55-gram laboratory mouse is exposed to a dose of 20.5 rad of radiation, how much energy is absorbed by the mouse’s body?

Verified step by step guidance

1. Understand that 1 rad is equivalent to 0.01 joules of energy absorbed per kilogram of tissue.
2. Calculate the mass of the mouse in kilograms by converting grams to kilograms. (55 grams = 0.055 kilograms)
3. Use the formula: Energy absorbed (in joules) = dose (in rads) × mass (in kg) × 0.01 J/kg per rad.
4. Substitute the given values into the formula: Energy absorbed = 20.5 rads × 0.055 kg × 0.01 J/kg per rad.
5. Perform the multiplication to find the energy absorbed in joules.

Key Concepts

Radiation Dose

Radiation dose, measured in units such as rad, quantifies the amount of energy absorbed by a material, typically biological tissue, from ionizing radiation. One rad is defined as the absorption of 100 ergs of energy per gram of tissue. Understanding this concept is crucial for calculating the energy absorbed by the mouse based on its mass and the radiation dose it receives.

Energy Absorption Calculation

To determine the energy absorbed by an object from radiation, the formula used is: Energy (in ergs) = Dose (in rads) × Mass (in grams). This relationship allows for the straightforward calculation of energy absorbed by multiplying the radiation dose by the mass of the object, which in this case is the laboratory mouse.

Unit Conversion

In scientific calculations, it is often necessary to convert units to ensure consistency and accuracy. For example, while energy may be expressed in ergs, it can also be converted to joules (1 erg = 10^-7 joules). Understanding unit conversion is essential for interpreting results and ensuring that calculations align with standard scientific practices.