Joules =mass over a distance
11N*0.3m=3.3 Joules
efficiency= energy out/energy in *100%
energy out =energy of the tool=3 J
Energy in = added energy (man)=3.3 J
3/3.3*100%=90.91%
Answer:
B: The colors of light emitted from heated atoms had very specific energies.
Explanation:
In Thompson's model of an atom the atom is said to be constituted of electrons which are surrounded by a haze of positive charge in order to balance the electrons' negative charges. It is also called plum prodding model because of negatively charged plums which are surrounded by the positively charged pudding.
Now, as the electrons move from higher to lower energy levels a photon which is a particle of light will be given off.
Thus, the correct answer is option B
Answer:
You can describe the<u> motion </u>of an object by saying it is moving in a straight line or is curved around another object. You can also describe where an object is by its <u> position </u> in relation to another object. The second object acts as a<u> reference</u> point. When an object changes position, you know it has motion. Motion can also be described by finding an object's <u>speed </u>or how fast or slow it moves in a certain amount of time. In addition, you can describe the object's speed AND direction together. This is called <u>velocity</u>
Explanation:
In the given answer-
<u>Motion</u> is defined as - the change in the movement or position of any object or body.
<u>Position</u> is said to be a place or somewhere or a location where any object or body is particularly placed/located or put on.
<u>Reference poin</u>t is a fixed point with regards to which any object or body changes its position. It is also called reference origin.
<u>Speed</u> is defined as the rate of any object covering certain distances. It is a scaler quantity (quantity which depends upon only magnitude).
<u>Velocity</u> is defined as the rate of speed per unit time. It is a vector quantity (quantity depending upon both magnitude and direction ).
Answer:
The acceleration of the cart is 1.0 m\s^2 in the negative direction.
Explanation:
Using the equation of motion:
Vf^2 = Vi^2 + 2*a*x
2*a*x = Vf^2 - Vi^2
a = (Vf^2 - Vi^2)/ 2*x
Where Vf is the final velocity of the cart, Vi is the initial velocity of the cart, a the acceleration of the cart and x the displacement of the cart.
Let x = Xf -Xi
Where Xf is the final position of the cart and Xi the initial position of the cart.
x = 12.5 - 0
x = 12.5
The cart comes to a stop before changing direction
Vf = 0 m/s
a = (0^2 - 5^2)/ 2*12.5
a = - 1 m/s^2
The cart is decelerating
Therefore the acceleration of the cart is 1.0 m\s^2 in the negative direction.
A person runs up 40 stairs and then come down 10 steps
So total stairs upwards is given as
now here we will have total height reached
Now total energy used or mechanical work done is
Now the mechanical power is given as
