Answer:
v = 26.7 mph
Explanation:
During the first 5 hours, at a constant speed of 20 mph, we find the total displacement to be as follows:
Δx₁ = v₁*t₁ = 20 mph*5 h = 100 mi
Assuming we can neglect the displacement during the speeding up from 20 to 60 mph, we can find the the total displacement at 60 mph as follows:
Δx₂ = v₂*t₂ = 60 mph*1 h = 60 mi
So, the total displacement during all the trip wil be:
Δx = Δx₁ + Δx₂ = 100 mi + 60 mi = 160 mi
So we can find the the average velocity during the 6-hour period, applying the definition of average velocity, as follows:
v = Δx / Δt = 160 mi / 6 h = 26.7 mph
Answer:
P = 97.2 W
Explanation:
Given that,
Voltage drop, V = 54 V
The resistance of the resistor, R = 20 Ohms
Current, I = 1.8 A
We need to find the power used by the resistor. The formula used to find the power is given by :
P = VI
Putting all the values,
P = 54 V × 1.8 A
P = 97.2 W
So, the power used by the resistor is 97.2 W.
Answer:
168 seconds (2 min 48 s)
Explanation:
Find the heat absorbed by the water.
q = mCΔT
q = (1 kg) (4200 J/kg/K) (70°C − 40°C)
q = 126,000 J
Power is energy per time.
P = q / t
750 W = 126,000 J / t
t = 168 s
It takes 168 seconds (2 min 48 s).
Answer:
692.31 N
Explanation:
Applying,
F = ma............... Equation 1
Where F = Average force required to stop the player, m = mass of the player, a = acceleration of the player
But,
a = (v-u)/t............ Equation 2
Where v = final velocity, u = initial velocity, t = time.
Substitute equation 2 into equation 1
F = m(v-u)/t............ Equation 3
From the question,
Given: m = 75 kg, u = 6.0 m/s, v = 0 m/s (to stop), t = 0.65 s
Substitute these values into equation 3
F = 75(0-6)/0.65
F = -692.31 N
Hence the average force required to stop the player is 692.31 N
No, options are given but I believe the answer would be
In a water cycle Solid state of matter has the particles closest together.
