Answer:
Total weight of the hot tub and water is 5676.6 pounds-force
Explanation:
rho = 62.4lbm/ft^3 × 1ft^3/7.481gal = 8.34lbm/gal
Mass of water = rho × volume = 8.34lbm/gal × 600 gallons = 5004lbm = 5004×0.45359kg = 2269.8kg
Total mass of hot tub and water = 320kg + 2269.8kg = 2589.8kg
Local acceleration due to gravity = 32ft/s^2 = 32ft/s^2 × 1m/3.2808ft = 9.75m/s^2
Total weight of hot tub and water = 2589.8kg × 9.75m/s^2 = 25250.55N = 25250.55/4.4482 lbf = 5676.6 lbf
<h2>
The impact is occurred at a distance 348.55 m far from person.</h2>
Explanation:
Let s be the distance to the impact position and t be the time when he hears the sound though concrete after impact.
Time when he hears impact through air = t + 0.90
The distance traveled by sound wave in both concrete and air is s.
Speed of sound in air = 343 m/s
Speed of sound in concrete = 3000 m/s
Distance traveled in air = Distance traveled in concrete
343 x Time when he hears impact through air = 3000 x Time when he hears impact through concrete
343 x (t + 0.90) = 3000 x t
3000t - 343 t = 343 x 0.90
2657t = 308.7
t = 0.116 s
Distance traveled in concrete = 3000 x t = 3000 x 0.116 = 348.55m
So the impact is occurred at a distance 348.55 m far from person.
Answer:
Coefficient of static friction required = 0.94
Explanation:
Coefficient of static friction required 
Velocity, v = 120 km/h = 33.33 m/s
g = 9.81 m/s²
R = 120 m
Coefficient of static friction required
Coefficient of static friction required = 0.94
Answer:
1600 N
Explanation:
F-F' = ma.................. Equation 1
Where F = Force exerted by the engine, F' = Frictional Force, m = mass of the car, a = acceleration of the car.
make F' the subject of the equation
F' = F-ma............... Equation 2
Given: F = 1600 N, m = 880 kg, a = 0 m/s (moving with a constant velocity).
Substitite these values into equation 2
F' = 1600+880(0)
F' = 1600 N.