There is no medium for the sound waves to travel through
Answer: - 7500N
Explanation:
Given the following :
Initial Velocity of car = 108km/hr
Time taken to stop after applying brakes = 4s
Mass of passengers in car = 1000kg
Force exerted by the brakes on the car =?
After 4s, then final Velocity (V) = 0
Initial Velocity (u) of the car = 108km/hr
108km/hr = (108 × 1000)m ÷ (3600)s = 30m/s
Force exerted = mass(m) × acceleration(a)
Acceleration of car = Change in Velocity with time
a = (v - u) / t
a = (0 - 30) / 4
a = - 30/ 4
a = - 7.5m/s^2
Therefore,
Force exerted = mass(m) × acceleration(a)
Force exerted = 1000kg × (-7.5)m/s^2
Force exerted = - 7500N
Answer:
1. 
2. 
Explanation:
Given:
length of copper cable, 
diameter of copper cable, 
current through the copper wire, 
We have the resistivity of copper, 
<u>We know that the resistance of a wire is given as:</u>
where:
cross sectional area of the wire
1.
<u>Now from the Ohm's law:</u>
2.
<u>From the Joules law the thermal energy generated as an effect of electrical energy is mathematically given as:</u>
<u />
where:
time duration for which the current flows
(∵ we have 3600 seconds in 1 hour)
Answer:
v=3.66,h-3.66
Explanation:
vertical = 10sin60 - 10sin 30
horizontal =10cos60 + 10cos 30
v = 10×0.8660-10×0.5
h = 10×0.5 + 10 × 0.8660
v=8.660-5.0 = 3.66
h= 5.0-8.660 = -3.66
Answer:
0 J
Explanation:
The mass is not moving, therefore the kinetic energy is 0.
(I had this same question and the answer is 0)
