Answer: Friction
Explanation:
Friction is a force that opposes the motion of an object on another surface. For example, when a box is pushed along the floor, the floor exerts a frictional force on the box, "resisting" the motion of the box. This force is due to the contact between the molecules of the box and the molecules of the floor, and it is always directed against the direction of motion of the object (so, if the object is moving forward, friction acts backwards).
The magnitude of the friction force is given by:
where is the coefficient friction, which is a number that depends on the materials of the two surfaces, and N is the normal reaction.
To answer this item, it is assumed that the gas in the cylinder is ideal such that it follows the equation,
PV = nRT
when V is to be calculated,
V = nRT/P
V = (4)(0.0821 L.atm/molK)(300 K) / (400 kPa/101.325 kPa/atm)
V = 24.95 L
Thus, the volume of gas in the cylinder is 24.95 L.
<h3><u>Answer</u>;</h3>
A) 84 calories
<h3><u>Explanation</u>;</h3>
- Specific Heat Capacity is the energy, transferred as heat, that is required to raise the temperature of one gram of a substance by one degree Celsius.
- Quantity of heat = mcΔt; Where m is the mass in kilograms, c is the specific heat capacity and Δt is the change in temperature.
<em>Mass = 10 g, specific heat capacity = 0.21 cal g°C, and Δt = 10 °C</em>
<em>Therefore;</em>
<em>Heat = 10 × 0.21 cal g°C × 40 °C</em>
<em> = </em><u><em>84 calories</em></u><em> </em>