<em>Choice-C</em> is the right one.
-- The bolt didn't react to the magnet, and just laid there. That tells you that the bolt was made of a non-magnetic material.
-- The bolt didn't float. It went straight to the bottom. That tells you that it's more dense than the fluid around it.
A dummy is fired vertically upward from a canon with a speed of 40 m/s. How long is the dummy in the air? What is the dummies maximum height?
v=u-at
0=40-10xt
t=4 secs
height = ut-1/2at^2
height= 40x4-1/2x10x4^2
height = 160-5x16
height=160-80=80m
Answer: 13 m/s
Explanation: The two vectors form a 5-12-13 right triangle. the magnitude of their resultant is the hypotenuse, which is 13 m/s.
a) KE=0.5*mv^2==0.5*145*25^2=45312.5 J
b) PE=mgh=145*9.8*3.5=4973.5 J
c) ME=KE+PE=m(0.5v^2+gh)=62524 J
Answer:
The boat is approaching at 0.9938 m/s to the dock when it is 9 m from the dock.
Explanation:
α=tan⁻¹(1 m / 9 m)
α= 6.34º
V= 1m/s
Vx = V * cos (6.34º)
Vx= 0.9938 m/s