Answer:
c.
Explanation:
From the options provided the best description of scissor is that scissors helps to scrap things down. This is the main purpose of scissors, to cut things, and by doing so you are breaking up a larger object into smaller and more manageable scraps. We can get rid of the other options because scissors are made of metal and therefore not soft and are not necessarily dull since they need to be sharp to fulfill their purpose. Although a pair of scissors has two holes it is not necessarily the best description of it.
55 J
Explanation:
Kinetic energy is given as: 0.5MV^2 where M is the mass and V is the speed of rotation. Since the masses are point masses, we calculate the point mass for each mass.
M1 = 30*0.2^2 = 1.2kgm^2
M2 = 20*0.4^2 = 3.2kgm^2
V = 5 rad/s
Calculating using the formula above, we obtain :
0.5(1.2+3.2)5^2 =0.5*4.4*25 = 55 J
Answer: 1.289 m
Explanation:
The path the cobra's venom follows since it is spitted until it hits the ground, is described by a parabola. Hence, the equations for parabolic motion (which has two components) can be applied to solve this problem:
<u>x-component:
</u>
(1)
Where:
is the horizontal distance traveled by the venom
is the venom's initial speed
is the angle
is the time since the venom is spitted until it hits the ground
<u>y-component:
</u>
(2)
Where:
is the initial height of the venom
is the final height of the venom (when it finally hits the ground)
is the acceleration due gravity
Let's begin with (2) to find the time it takes the complete path:
(3)
Rewritting (3):
(4)
This is a quadratic equation (also called equation of the second degree) of the form 
, which can be solved with the following formula:
(5)
Where:
Substituting the known values:
(6)
Solving (6) we find the positive result is:
(7)
Substituting (7) in (1):
(8)
We finally find the horizontal distance traveled by the venom:
Answer:
I think it's D. The expansion of water as it freezes increases the amount of nutrients that can dissolve in liquid water, but it could cause fluid in cells to dissolve more harmful substances.
Explanation:
I know when water freezes, it expands and between the two answers that discuss the expansion of water, D sounds the most logical to me lol.
