Answer:
The average velocity is 50 km/h south
Explanation:
The average velocity of an object is its total displacement divided by
the total time taken.
That means it is the rate at which an object changes its position from
one place to another.
Average velocity is a vector quantity.
The SI unit is meters per second.
A bicycle that starts 100 km south and is 120 km south of town after
0.4 hour.
The displacement = 120 - 100 = 20 km south
The time = 0.4 hour
The average velocity =
, where D is the displacement
and t is the time
The average velocity of the bicycle =
km/h
<em>The average velocity is 50 km/h south</em>
If you want it in meter per second, change the kilometer to meter
and change the hour to seconds
1 km = 1000 m
1 hour = 60 × 60 = 3600 seconds
The average velocity of the bicycle =
m/s south
calculate the power per hour of a radiator, knowing that it is connected to a common 110 v contact. and requires 20 Amp.
Answer:
2.2kWh
Explanation:
Given parameters:
Potential difference = 110v
Current = 20A
Unknown:
Power = ?
Solution:
To solve this problem, we use the expression below:
Power = IV
Power = 110 x 20 = 2200W
This is therefore 2.2kW
Power per hour = 2.2kWh
Answer:
v = √ 2 G M/
Explanation:
To find the escape velocity we can use the concept of mechanical energy, where the initial point is the surface of the earth and the end point is at the maximum distance from the projectile to the Earth.
Initial
Em₀ = K + U₀
Final
= 
The kinetic energy is k = ½ m v²
The gravitational potential energy is U = - G m M / r
r is the distance measured from the center of the Earth
How energy is conserved
Em₀ = 
½ mv² - GmM /
= -GmM / r
v² = 2 G M (1 /
– 1 / r)
v = √ 2GM (1 /
– 1 / r)
The escape velocity is that necessary to take the rocket to an infinite distance (r = ∞), whereby 1 /∞ = 0
v = √ 2GM /
Answer:
4 s
Explanation:
Given:
Δx = 12 m
v₀ = 6 m/s
v = 0 m/s
Find: t
Δx = ½ (v + v₀) t
12 m = ½ (0 m/s + 6 m/s) t
t = 4 s
Answer:
The store energy in the inductor is 0.088 J
Explanation:
Given that,
Inductor = 100 mH
Resistance = 6.0 Ω
Voltage = 12 V
Internal resistance = 3.0 Ω
We need to calculate the current
Using ohm's law


Put the value into the formula


We need to calculate the store energy in the inductor



Hence, The store energy in the inductor is 0.088 J