Answer:
a) v = 54.7m/s
b) v = (58 - 1.66a) m/s
c) t = 69.9 s
d) v = -58.0 m/s
Explanation:
Given;
The height equation of the arrow;
H = 58t - 0.83t^2
(a) Find the velocity of the arrow after two seconds. m/s;
The velocity of the arrow v can be given as dH/dt, the change in height per unit time.
v = dH/dt = 58 - 2(0.83t) ......1
At t = 2 seconds
v = dH/dt = 58 - 2(0.83×2)
v = 54.7m/s
(b) Find the velocity of the arrow when t = a. m/s
Substituting t = a into equation 1
v = 58 - 2(0.83×a)
v = (58 - 1.66a) m/s
(c) When will the arrow hit the surface? (Round your answer to one decimal place.) t = s
the time when H = 0
Substituting H = 0, we have;
H = 58t - 0.83t^2 = 0
0.83t^2 = 58t
0.83t = 58
t = 58/0.83
t = 69.9 s
(d) With what velocity will the arrow hit the surface? m/s
from equation 1;
v = dH/dt = 58 - 2(0.83t)
Substituting t = 69.9s
v = 58 - 2(0.83×69.9)
v = -58.0 m/s
Pipettors, microcentrifuge, timers, mixers, a water bath. And those should only be used for radioactive materials (sorry if this is wrong it’s my best knowledge for this stuff :/)
Hello there!
Plastic is definitely off. Plastic can melt easily in extreme heat, and if it doesn't melt, the chemicals used to create it will seep into the food. D is false.
Aluminum is off too, if we're talking about heating up food in a microwave. Aluminum can spark in the heat and can catch fire/explode in most cases. So that would also be off.
Foam is off as well. Whether it be foam bubbles or foam board, it's probably NOT a good idea to hear up your food in the microwave with foam.
But ceramic would probably be the best choice. Ceramic is microwave safe, it doesn't melt, catch fire, or seep chemicals in the food when placed in that kind of heat. That is probably why a lot of manufacturers use ceramic glass to make plates and bowls in the first place.
So your answer should be B. Ceramic. Hope this helped you! :)
Formula for velocity:
V(t) = Vi + at
Where V(t) is velocity at time t, Vi is initital velocity, and a is acceleration.
Solving for a:
V(8) = Vi + a(8)
V(8) = 0 (car has stopped)
0 = 24 + 8a
-24 = 8a
a = -3 m/s/s