Molecular formula of water molecule is H₂O.
The bodies of arthropods are supported, not by internal bones, but by a hardened exoskeleton<span> made of </span>chitin<span>, a substance produced by many non-arthropods as well. In arthropods, the nonliving exoskeleton is like a form-fitting suit of armor. It is produced by the "skin" and then hardens into a protective outer-covering.</span>
<h3>
Answer:</h3>
49 N
<h3>
Explanation:</h3>
<u>We are given;</u>
- Mass of the brick as 3 kg
- The coefficient of friction as 0.6
We are required to determine the force that must be applied by the woman so the brick does not fall.
- We need to importantly note that;
- For the brick not to fall the, the force due to gravity is equal to the friction force acting on the brick.
- That is; Friction force = Mg
But; Friction force = μ F
Therefore;
μ F = mg
0.6 F = 3 × 9.8
0.6 F = 29.4
F = 49 N
Therefore, she must use a force of 49 N
Answer:
Explanation:
Generally, length of vector means the magnitude of the vector.
So, given a vector
R = a•i + b•j + c•k
Then, it magnitude can be caused using
|R|= √(a²+b²+c²)
So, applying this to each of the vector given.
(a) 2i + 4j + 3k
The length is
L = √(2²+4²+3²)
L = √(4+16+9)
L = √29
L = 5.385 unit
(b) 5i − 2j + k
Note that k means 1k
The length is
L = √(5²+(-2)²+1²)
Note that, -×- = +
L = √(25+4+1)
L = √30
L = 5.477 unit
(c) 2i − k
Note that, since there is no component j implies that j component is 0
L = 2i + 0j - 1k
The length is
L = √(2²+0²+(-1)²)
L = √(4+0+1)
L = √5
L = 2.236 unit
(d) 5i
Same as above no is j-component and k-component
L = 5i + 0j + 0k
The length is
L = √(5²+0²+0²)
L = √(25+0+0)
L = √25
L = 5 unit
(e) 3i − 2j − k
The length is
L = √(3²+(-2)²+(-1)²)
L = √(9+4+1)
L = √14
L = 3.742 unit
(f) i + j + k
The length is
L = √(1²+1²+1²)
L = √(1+1+1)
L = √3
L = 1.7321 unit
From Newton's second law, we know F = ma, where a is the acceleration and m is the mass in kg.
F = 1000kg * 9.8m/s = 9800N
F = 9800 N
Hope this helps!
