Question

Indicate whether each item is true or false. If an item is false, please correct it so that it is true.

1. Speed is a scalar quantity. Work and energy are vector quantities.
2. Objects that are not moving cannot have any work done to them.
3. Pressure is uniform throughout a fluid, regardless of depth
4. Density of a material changes as the temperature of the material changes.
5. Solids are always more dense than liquids. Liquids are always more dense than gases
6. Falling objects see their gravitational potential energy converted to kinetic energy.
7. A 40 kg child sliding down a 45˚ frictionless slide that is 4 m above the ground will be going slower than a 40 kg child sliding down a 60˚ frictionless slide that is 4 m above the ground
8. Objects falling in water can reach terminal velocity faster than objects falling in air.
9. When an object is not moving, it must not have any forces acting on it.
10. Crumple zones reduce the force transmitted to occupants in a car by reducing the time it takes for damage to be absorbed in an accident.
11. Impulse is equivalent to momentum. Work is equivalent to energy.
12. The force of friction acts in the opposite direction as work being done on the object.
13. When an object is sitting on an incline, the full force of gravity is equal to (but opposite) the normal force.
14. Two men are racing around a curve with a radius of 12 m. They are traveling at a velocity of 15 m/s. If the first man has twice the mass of the second, then his centripetal acceleration will be four times as much.
15. The buoyant force acting on an object is equal to the weight of the water the object displaces.

Answer 1

Sota @ Speed is a Scalcev quantity. Gork and enexgyar (True) B) work and Energy are vector quantities. (False, they are also Scolar quantity) (C) pressure is coniform throughout a fleid, gegardless og depth. ( Falle, postlene increase with depth) (1) Density of material changes as the temp. of maksial changes. I Truel e) Solide are always more dense than liquid. Liquido are always more dense than gares. (Falle, sometimes density g solid is less than liquid. Exrice) D) Falling objects See gravitational pot energy converted to. Kinetic energy. True) (9) A 40 Kg Child Sliding at 45• Jesictionless Slide that is Um above ground colll be going I lower than a Lokg Child Sliding ducon a 6oo foictionles slide that is um from the ground. I Featre True, i aagsince So, frost child coill experience less acceleration as LS°C 60°) (h) objects falling in water can reach terminal Velocity faster than objects falling in arr. (True) li) eohen an object is not moving, it must not have any force acting on it. I false, it may or may not have any forces acting on it).

U crumple Zone reduce the force transmitted to occupants in a car by reducing the time it take for damage to be absorbed in an acciolent. (Toue) (K) Impulse is equivalent to momentum. Cork is equivalent to energy. Litoue) The force of frichon acts in opp.dern as work being done on the object. (true). (m) Cohen an object is sitting on an incline, the face forle g gravity is equal to ( beel opp. I the normal force. (False, Na mg cos co cohere Q is angle of incline) Two men are racing around a curve with a radice of 12 mm. They are travelling at vel. 15 mls. If the first man has twice the mass of second, then his centripetal accen cuill be four time as much. ( False Gc= mv2 so, centripetal accen coull be twice as much) s The buoyant force acting on an object is equal to the weight of the water the object displace. (Tone)