Answer:
p = -8 kg-m/s
Explanation:
Given that,
Initial speed of the rock, u = 8 m/s
Mass of the rock, m = 1 kg
The ball travels up to a maximum height, then returns to the ground.
We need to find the rock's momentum as it strikes the ground. Let v be the final speed of the rock. Its final speed is as same as initial speed i.e. 8 m/s but in negative direction. So
p = mv
p = 1 kg × (-8 m/s)
= -8 kg-m/s
So, the rock's momentum as it strikes the ground is (-8 kg-m/s).
You have said that 15cm³ of gold weighs 2.8N. So I may infer that each cm³
of gold weighs about 0.19N. When I compare that figure with the 0.13N per cm³
of mercury, it becomes immediately apparent that the gold is more dense than
mercury. Therefore, the sample of gold, no matter what its size or weight, will
displace its total volume of mercury, and will go on to sink entirely beneath the
waves in the mercury.
Answer:
4.28 s
Explanation:
after two seconds (2 s) His friends is
d = 3.5 m/s x 2 s = 7 meter ahead.
in this state, a bicylist start from initial velocity vo = 0 m/s and accelerat 2.4 m/s²
then, when bicylist reach his friend
t friend = t bicyclist = t
d bicylist = d friend + d
-------
d friend = 3.5 . t
d bicylist = vo . t + ½ a t²
d friend + d = vo . t + ½ a t²
3.5 t + 7 = 0 . t + ½ . 2.4 . t²
3.5 t + 7 = 1.2 t²
0 = 1.2 t² - 3.5 t - 7
t = -1.363 and t = 4.28
take the positive one
Answer:
It would change the amount of heat produced in the transmission line to four times the previous value.
Explanation:
Given;
initial voltage in the transmission line, V₁ = 500 kV = 500,000 V
Final voltage in the transmission line, V₂ = 1 MV = 1,000,000
The power lost in the transmission line due to heat is given by;
Power lost in the first wire;
Power lost in the second wire
Keeping the resistance constant, we will have the following equation;
Therefore, it would change the amount of heat produced in the transmission line to four times the previous value.