Answer:
Time, t = 13.34 seconds.
Explanation:
Given the following data;
Initial velocity, u = 85km/hr to meters per seconds = 85*1000/3600 = 23.61 m/s
Final velocity, v = 45km/hr to meters per seconds = 45*1000/3600 = 12.5 m/s
Acceleration, a = -3 km/hr/sec to meters per seconds square = -3*1000/3600 = -0.833m/s²
To find the time;
Acceleration = (v - u)/t
-0.833 = (12.5 - 23.61)/t
-0.833t = -11.11
t = 11.11/0.833
Time, t = 13.34 seconds.
Answer:
1.5 kgms⁻¹
Explanation:
Momentum can be defined as "<em>mass in motion</em>."
The amount of momentum that an object has is dependent upon two factors
- mass of the moving object
when there is a change in the velocity , it creates a change in momentum also
when we consider that we can mathematically show this,In terms of an equation,
Change in momentum (ΔΡ) = m(Δv)
where (Δv) - change in velocity
<em>(Δv) = final velocity - initial velocity</em>
Change in momentum (ΔΡ) = m(Δv)
= 0.1×([55-40])
= 1.5 kgms⁻¹
Answer:
4.98 m
Explanation:
Given that
Width of the mirror, d = 0.6 m
Organist distance to the mirror, s = 0.78 m
Distance between the singer and the organist, S = 5.7 + 0.78 = 6.48 m
Width of north wall, D?
Using the simple relationship
D/S = d/s, on rearranging
D = dS /s
D = (0.6 * 6.48) / 0.78
D = 3.888 / 0.78
D = 4.98 m
Therefore, we can conclude that the Width of north wall is 4.98 m
The correct options are:
D
"Radio waves have a lower frequency, which makes them safer for humans."
B
"Radio waves take less energy to produce."
<h3>
Why do we radio waves over other electromagnetic waves to transmit information to Earth? </h3>
Radio waves are electromagnetic waves with frequencies on the range from 10 KHz to 10 THz.
Now, remember that all electromagnetic waves have the same speed, which is the speed of light, and the energy of a wave is proportional to its frequency.
Particularly, we can see that radio waves have small frequencies (smaller than infrared light) so these waves carry very little energy.
With that in mind, the correct options are.
D
"Radio waves have a lower frequency, which makes them safer for humans."
B
"Radio waves take less energy to produce."
These are the two main reasons of why we use radio waves.
If you want to learn more about electromagnetic waves.
brainly.com/question/14015797
#SPJ1
To solve this problem, we must remember about the law of
conservation of momentum. The initial momentum mist be equal to the final
momentum, that is:
m1 v1 + m2 v2 = (m1 + m2) v’
where v’ is the speed of impact
Since we are not given the masses of each car m1 and m2,
so let us assume that they are equal, such that:
m1 = m2 = m
Which makes the equation:
m v1 + m v2 = (2 m) v’
Cancelling m and substituting the v values:
50 + 48 = 2 v’
2 v’ = 98
v ‘ = 49 km/h
<span>The speed of impact is 49 km/h.</span>
