Answer:
d. 60
Explanation:
If a body of mass 2 kg is moving with a velocity of 30 m/s, then
on doubling its velocity the momentum becomes
a 30 kgm/s
b 90 kgm/s
C 120 kgm/s
d 60 kgm/s
HALPLPLPPLL
Answer:
a) a = 0.477 m/s^2
b) u = 0.04862
Explanation:
Given:-
- The rotational speed of the turntable N = 33 rev/min
- The watermelon seed is r = 4.0 cm away from axis of rotation.
Find:-
(a) Calculate the acceleration of the seed, assuming that it does not slip. (b) What is the minimum value of the coefficient of static friction between the seed and the turntable if the seed is not to slip
Solution:-
- First determine the angular speed (w) of the turntable.
w = 2π*N / 60
w = 2π*33 / 60
w = 3.456 rad/s
- The watermelon seed undergoes a centripetal acceleration ( α ) defined by:
α = w^2 * r
α = 3.456^2 * 0.04
α = 0.477 m / s^2
- The minimum friction force (Ff) is proportional to the contact force of the seed.
- The weight (W) of the seed with mass m acts downwards. The contact force (N) can be determined from static condition of seed in vertical direction.
N - W = 0
N = W = m*g
- The friction force of the (Ff) is directed towards the center of axis of rotation, while the centripetal force acts in opposite direction. The frictional force Ff = u*N = u*m*g must be enough to match the centripetal force exerted by the turntable on the seed.
Ff = m*a
u*m*g = m*a
u = a / g
u = 0.477 / 9.81
u = 0.04862
Explanation:
The frequency is given to be f = 8 Hz.
Period is the inverse of frequency.
T = 1/f = 0.125 s
Velocity is wavelength times frequency.
v = λf = (0.40 m) (8 Hz) = 3.2 m/s
The wave travels 3.2 meters every second.
Nitrogen
Explanation:
Adding one proton to a carbon atom makes Nitrogen.
A quick introspection on atoms:
- An atom is made up of three fundamental particles.
- They are protons, neutrons and electrons.
- The protons are positively charged and the neutrons do not carry any charges.
- Electrons are negatively charged.
The difference between an atom and another is the number of protons in them. This is the atomic number.
The periodic table of element is a list of elements arranged based on the number of protons they have. Every element on the table has unique number of protons which makes it differ from another.
- Atoms do not readily lose their protons because they are held by nuclear forces in the nucleus of an atom.
When an element gains a proton, it becomes another element.
Carbon has proton number of 6
If a proton is added to it, it becomes 7
This is the proton or atomic number of nitrogen.
Learn more:
Atomic number brainly.com/question/5425825
#learnwithBrainly
A concave mirror is an example of curved mirrors. So that the appropriate answer to the given question is option D. The rays will cross at the focal point.
A concave mirror is a type of mirror in which its inner part is the reflecting surface, while its outer part is the back of the mirror. This mirror reflects all parallel rays close to the principal axis to a point of convergence. It can also be referred to as the converging mirror.
In this type of mirror, all rays of light parallel to the principal axis of the mirror after reflection will cross at the focal point.
Therefore, the required answer to the given question is option D. i.e The rays will cross at the focal point.
For reference: brainly.com/question/20380620
