As per the question the total distance is given as 4 km.
We are asked to calculate the average speed.
The time taken by the body to travel each kilometre are 5.9 min,6.2 min.,6.3min. and 6 min. respectively.
The average speed of a body is defined as the ratio of total distance travelled by the body to the total time.
Mathematically the average speed is written as _
V= Total distance/Total time
i.e V = S/T
Where S is the total distance travelled and T is the total time
Here total distance (S)= 4 km
The total time T= (5.9+6.2 +6.3+ 6.0 )minutes
=24.4 min.
Hence average speed V = 4 km/24.4 min
= 0.16 km/min.
Hence the correct option is A .
Answer: The recoil speed is - 8.9604.
m/s.
Explanation: According to the Third Law of Newton, every action has an oppsite and equal reaction, and the Second Law of Newton, Force=mass·acceleration. Acceleration is a variation in velocity by any given time, so Force = mass·velocity·time.
Combining the two laws, there is : m1·v1 = - m2·v2. This is the Law of Conservation of Momentum.
Substituting and calculating:
v2 = - (
) · v1
v2 = - 
· 5.24.
v2 = - 8.9604.
The recoil speed of the thorium nucleus is - 8.9604.m/s.
Answer:
6.75×10^13N
Explanation:
The electric force between the charges can be determined using coulombs law which states that 'the force of attraction between two charges is directly proportional to the product of the charges and inversely proportional to the square of their distance between them.
Mathematically, F = kq1q2/r² where;
q1 and q2 are the charges
r is the distance between the charges
F is the force of attraction
k is the coulombs constant
Given q1 = 5C q2 = 15C r = 10cm = 0.1m k = 9×10^9Nm²/C²
Substituting the given values in the formula we have;
F =9×10^9×5×15/0.1²
F = 6.75×10^11/0.01
F = 6.75×10^13N
Therefore the electric force between them is 6.75×10^13N
Take wire and a nail strip 2 in of wire then wrap it around a nail
