Answer:
11.27N
Explanation:
Given parameters:
Mass of the book = 1.15kg
Unknown:
Magnitude of the normal force = ?
Solution:
The normal force is the vertical force exerted by a body on an object.
It can be described as the weight of an object.
Normal force = mass x acceleration due to gravity
Normal force = 1.15 x 9.8 = 11.27N
Answer:
the quantity of matter contained in a body is called mass .si unit of mass is kilogram.weight is effected by gravity but mass is not effected by gravity.
Incomplete question.The Complete question is here
A flat uniform circular disk (radius = 2.00 m, mass = 1.00 ✕ 102 kg) is initially stationary. The disk is free to rotate in the horizontal plane about a friction less axis perpendicular to the center of the disk. A 40.0-kg person, standing 1.25 m from the axis, begins to run on the disk in a circular path and has a tangential speed of 2.00 m/s relative to the ground.
a.) Find the resulting angular speed of the disk (in rad/s) and describe the direction of the rotation.
b.) Determine the time it takes for a spot marking the starting point to pass again beneath the runner's feet.
Answer:
(a)ω = 1 rad/s
(b)t = 2.41 s
Explanation:
(a) initial angular momentum = final angular momentum
0 = L for disk + L............... for runner
0 = Iω² - mv²r ...................they're opposite in direction
0 = (MR²/2)(ω²) - mv²r
................where is ω is angular speed which is required in part (a) of question
0 = [(1.00×10²kg)(2.00 m)² / 2](ω²) - (40.0 kg)(2.00 m/s)²(1.25 m)
0=200ω²-200
200=200ω²
ω = 1 rad/s
b.)
lets assume the "starting point" is a point marked on the disk.
The person's angular speed is
v/r = (2.00 m/s) / (1.25 m) = 1.6 rad/s
As the person and the disk are moving in opposite directions, the person will run part of a revolution and the turning disk would complete the whole revolution.
(angle) + (angle disk turns) = 2π
(1.6 rad/s)(t) + ωt = 2π
t[1.6 rad/s + 1 rad/s] = 2π
t = 2.41 s
Answer:
D. Observations of constellations show that stars have moved over time.
Explanation:
A scientific claim is basically an observation in science.
Constellation changes there position over time because of earth's rotation around sun. So, observation of constellations shows that stars have moved over time is a scietific claim. If stars would not move then constellation will not form.
Hence, the correct answer is "of constellations show that stars have moved over time".
Answer:
<h3>The answer is 300 N</h3>
Explanation:
The force acting on an object given the mass and acceleration we use the formula
<h3>force = mass × acceleration</h3>
We have
force = 15 × 20
We have the final answer as
<h3>300 N</h3>
Hope this helps you
