Answer:
The statement is not correct.
Explanation:
To know if the statement is correct, we shall determine the velocity of the car after 3 s. This is illustrated below.
Data obtained from the question include:
Initial velocity (u) = 0 m/s
Acceleration due to gravity (g) = 9.8 m/s²
Time (t) = 3 s
Final velocity (v) =?
v = u + gt
v = 0 + (9.8 × 3)
v = 0 + 29.4
v = 29.4 m/s
Thus, the velocity of the car after 3 s is 29.4 m/s.
Hence, the statement made by the friend is not correct as the car has a falling velocity of 29.4 m/s after 3 s.
Answer:
Wavelenght is 4.53x10^-7m
Explanation:
Detailed explanation and calculation is shown in the image below
Answer:
We know that potential energy of a body;
= mass(m)× gravitational acceleration(g) × height(h)
Lets find out the mass of the body
P.E. = mgh
=> 6500J = mass × 9.8m/s^2 × 12m
=>6500J = mass × ( 9.8 × 12 ) × ( m/s^2 × m)
=> 6500 Nm = m × 117.6 × m^2 / s^2
=> 6500/117.6 Ns^2/m = mass [°.° Ns^2/m = kg]
=> 55.272 Kg = mass
Therefore the mass of the body = 55.272 kg ~ <em>6</em><em>0</em><em> </em><em>k</em><em>g</em><em> </em>(Ans)
Hope it helps you
Answer:
The scientific method is a method of research with defined steps that include experiments and careful observation. One of the most important aspects of this method is the testing of hypotheses by means of repeatable experiments. A hypothesis is a suggested explanation for an event, which can be tested.
Answer:
The crate's coefficient of kinetic friction on the floor is 0.23.
Explanation:
Given that,
Mass of the crate, m = 300 kg
One worker pushes forward on the crate with a force of 390 N while the other pulls in the same direction with a force of 320 N using a rope connected to the crate.
The crate slides with a constant speed. It means that the net force acting on it is 0. Net force acting on it is given by :

So, the crate's coefficient of kinetic friction on the floor is 0.23.