Physics - 1 - General Physics Questions & Answers

Physics - 1 - General Physics Questions & Answers concepts of momentum and impulse - ANSWER: The impulse means that the bigger the force and the longer it acts for, the bigger the impulse will be. Impulse of force = change of momentum Define acceleration - ANSWER: Acceleration is how quickly an objects velocity is changing, so if an object is moving around in a circle it is constantly accelerating because the direction is constantly changing Define efficiency - ANSWER: Efficiency is the percentage of energy or power that is converted into useful energy or power because no devise is 100% efficient, the energy converted always converts into wasted energy eg heat Define speed - ANSWER: A measure of how fast an object is travelling Define velocity - ANSWER: A measure of how fast an object is travelling with direction Define weight - ANSWER: Weight is a gravitational force Describe a manometer - ANSWER: A manometer measures pressure difference. The height difference shows the extra pressure that the gas supply has in addition to atmospheric pressure called excess pressure. To find the overall pressure you add the excess pressure (height of Mercury in mm to the atmospheric pressure which is 760mm) Whichever liquid is lower has more pressure on it so it pushes the other side of the liquid up. Describe circular motion in terms of acceleration - ANSWER: Because acceleration is change in velocity, an object moving in a circle is experiencing acceleration. Because the object is accelerating there is a resultant force acting upon it Describe circular motion in terms of velocity - ANSWER: Velocity is constantly changing because direction in constantly changing. Describe how to determine the density of a liquid - ANSWER: Measure the mass of a measuring cylinder then add the liquid to it and measure the mass taking away the mass of the measuring cylinder from the total mass. Then read the volume on the measuring cylinder and divide the mass by the volume Describe how to determine the density of a regular shaped solid - ANSWER: Measure the mass on scales and calculate the volume (area x height) then divide mass by volume Describe how to determine the density of an irregular shaped solid - ANSWER: Weigh the solid to collect mass. Then in a displacement can add water up to the level of the spout, add the solid into the can. As the water pours out of the spout collect it in a measuring cylinder. Then the