Answer:
--
Explanation:
All potential and kinetic energy is transferred into heat. Therefore keeping the law of conservation of energy valid. No energy is created nor destroyed only changing shape.
Answer:
6) False
7) True
8) False
9) False
10) False
11) True
12) True
13) True
14) True
Explanation:
The spacing between two energy levels in an atom shows the energy difference between them. Clearly, B has a greater value of ∆E compared to A. This implies that the wavelength emitted by B is greater than A while B will emit fewer, more energetic photons.
When atoms jump from lower to higher energy levels, photons are absorbed. The kinetic energy of the incident photon determines the frequency, wavelength and colour of light emitted by the atom.
The energy level to which an atom is excited is determined by the kinetic energy of the incident electron. As the voltage increases, the kinetic energy of the electron increases, the further the atom is from the source of free electrons, the greater the required kinetic energy of free electron. When electrons are excited to higher energy levels, they must return to ground state.
Answer:
1.
d
. A stream of particles
2. D. Radiowave
3. Microwaves
Answer: The spring constant is K=392.4N/m
Explanation:
According to hook's law the applied force F will be directly proportional to the extension e produced provided the spring is not distorted
The force F=ke
Where k=spring constant
e= Extention produced
h=2m
Given that
e=20cm to meter 20/100= 0.2m
m=100g to kg m=100/1000= 0.1kg
But F=mg
Ignoring air resistance
assuming g=9.81m/s²
Since the compression causes the plastic ball to poses potential energy hence energy stored in the spring
E=1/2ke²=mgh
Substituting our values to find k
First we make k subject of formula
k=2mgh/e²
k=2*0.1*9.81*2/0.1²
K=3.921/0.01
K=392.4N/m
speed of the car = 27 m/s
speed of truck ahead = 10 m/s
relative speed of car with respect to truck
relative deceleration of car
now the distance before they stop with respect to each other is given by
so it will come at the same speed of truck after 20.6 m distance and hence it will not hit the truck as the distance of the truck is 25 m from car
Part b)
Distance traveled by car before it stops is given by
so it will stop after it will cover total 52.1 m distance
Part c)
time taken by the car to stop
now the distance covered by truck in same time
now after the car will stop its distance from the truck is
<em>so the distance between them is 11.5 m</em>
