Answer:
Scenario 1 is the correct answer.
Explanation:
The sound of the drumstick hitting the metal bar will get to me in a shorter amount of time in Scenario 1 . The sound wave will travel faster in the metal bar than through the air because the speed of sound waves in solid is faster than it is in gases.
350 milliliters equals to .35 liters
Therefore, 3.5 times 10^-1 would be the only correct answer since that is the only one that matches .35 liters
How much work in J does the string do on the boy if the boy stands still?
<span>answer: None. The equation for work is W = force x distance. Since the boy isn't moving, the distance is zero. Anything times zero is zero </span>
<span>--------------------------------------... </span>
<span>How much work does the string do on the boy if the boy walks a horizontal distance of 11m away from the kite? </span>
<span>answer: might be a trick question since his direction away from the kite and his velocity weren't noted. Perhaps he just set the string down and walked away 11m from the kite. If he did this, it is the same as the first one...no work was done by the sting on the boy. </span>
<span>If he did walk backwards with no velocity indicated, and held the string and it stayed at 30 deg the answer would be: </span>
<span>4.5N + (boys negative acceleration * mass) = total force1 </span>
<span>work = total force1 x 11 meters </span>
<span>--------------------------------------... </span>
<span>How much work does the string do on the boy if the boy walks a horizontal distance of 11m toward the kite? </span>
<span>answer: same as above only reversed: </span>
<span>4.5N - (boys negative acceleration * mass) = total force2 </span>
<span>work = total force2 x 11 meters</span>
Answer:
C) 3,000 kg m/s
Explanation:
We can consider the horizontal velocity of the motorcycle to be zero, since it rolls off the edge of the cliff very slowly. So, we only need to find the vertical velocity at the time of the impact with the ground.
The vertical velocity of the motorcycle at time t is given by (free-fall motion):
where
is the initial vertical velocity (zero, since the motorcycle is not moving)
g = 9.8 m/s^2 is the acceleration due to gravity
t is the time
Since the motorcycle hits the ground after t = 3 seconds, we have
And since we know its mass, m=100 kg, we can find its momentum:
and the negative sign simply means downward direction.
Answer:
16.7 s
Explanation:
T= <u>Vf - Vo</u> a= <u>F</u>
a m
4,500 / 3000 = 1.5 (a)
30 - 5 / 1.5(a) = 16.7 s
