Answer:

Explanation:
From the question we are told that:
Density 
Frequency
Length
Generally the equation for Frequency is mathematically given by

Therefore



Answer:
option d) -9 J
Explanation:
Given:
Mass, m = 3.0 kg
time, t = 6.0 seconds
Velocity of mass, v = 2.0 m/s
height, h = 2 m
Now, using the concept of work-Energy theorem
we have
Net work done = change in kinetic energy
or
Work done by gravity + work done by the friction = Final kinetic energy - Initial kinetic energy
mgh +
= 
on substituting the values in the above equation, we get
3 × 9.8 × 2 +
= 
or
58.8 +
= 6
or
= -52.8 J
here negative sign depicts that the work is done against the motion of the mass
also,
Power = (Work done)/time
or
Power = -52.8/6 = -8.8 W ≈ 9 J
Hence, option d) -9 J is correct
Answer:

Explanation:
We are given that
Potential difference=V=154 V
Surface charge density=
Using 
We know that


Where

Using the formula


Using 
Hence, the spacing between the plates=
used cross breeding to purposely breed plan
studied a variety of pea plant traits
studied several generations of plants
In order to breed or cross one plant with another, Mendel opened the petals and removed the anthers from the flower and dusted the pistil with pollen from the plant he wished to cross it with and covered the flower with a small bag to prevent the pollen in the air from landing in the pistil. This process is called cross pollination.
Mendel considered 7 characters of pea plant for his study and did the study for several generations.
The correct answer is 19.72 °C. The first step is to determine the amount of heat that was lost per gram (30,000 J) / (390 g) = 76.92 J/g. Then to determine the temperature change, divide 76.92 J/g with the given specific heat of milk (76.92 J/g) / (3.9 J/g°C) = 19.72 °C.