Answer:
D. The speed of the combined vehicles is less than the initial speed of the truck.
Explanation:
Ik this is late
Answer:
Decrease
Explanation:
If you were on the Moon, which has significantly less mass than the Earth, your weight would: decrease
The point that seemed to be giving me a complicated time was being able to distinguish the difference and meaning of weight and mass and being able to apply that to a problem. I kept mixing up the definitions. For example in homework 3.1, one question asked:
If you were on the moon, which has significantly less mass than the earth, your mass would:
a. increase
b. decrease
c. stay the same
d. become zero
The definition of mass is the amount of matter in an object. The definition of weight is the amount or unit of force. For me, I just had to remember that when it asked about weight, it wasn’t referring how heavy an object is. After I was able to recognize that when it came to weight, questions became easier.
The final and correct answer was decreasing. The answer is because the Moon’s mass is less. This means the gravitational force is less on your body, therefore, your mass is going to be lighter
Answer:
132 N
Explanation:
Given that a 1.1 kg hammer strikes a nail. Before the impact, the hammer is moving at 4.5 m/s; after the impact it is moving at 1.5 m/s in the opposite direction. If the hammer is in contact with the nail for 0.025 s, what is the magnitude of the average force exerted by the hammer on the nail
From Newton 2nd law of motion,
Change in momentum = impulse.
Change in momentum = m( V - U )
Substitute all the parameters into the formula
Change in momentum = 1.1 ( 4.5 - 1.5 )
Change in momentum = 1.1 × 3
Change in momentum = 3.3 kgm/s
Impulse = Ft
That is,
Ft = 3.3
Substitute time t into the formula above
F × 0.025 = 3.3
F = 3.3 / 0.025
F = 132 N
Therefore, the magnitude of the average force exerted by the hammer on the nail is 132 N.
Answer:
For 6 its D
For 7 its A
For 8 its C
For 9 I think its B but Im not sure
Answer:
D) The velocity of the airplane must be greater than the speed of sound
Explanation:
Sonic boom is a phenomenon that occurs when an airplane travels ay a velocity greater than the speed of sound.
When this condition is met, the sound waves produced by the airplane (mainly from the engine) is not able to travel ahead of the plane, because the plane is moving at a greater speed than the sound itself; as a result, it is only transmitted behind the plane.
In this situation, a shock wave is produced. This shock wave is associated with a very loud "bang", that can be heard clearly even at several kilometers distance (in fact, supersonic planes are normally not allowed to fly over residential areas. In the past, for example the Concorde, was only allowerd to fly at supersonic speed over the ocean).
So the correct answer is
D) The velocity of the airplane must be greater than the speed of sound
