Answer:
If a car skids 66 ft on wet concrete, it will move at 243 ft/s when the brake is applied.
Explanation:
To determine how fast the car was moving, after skidding, the formula below is used:
V = √32*fd
V is the car's speed (ft/s)
d is skid length (ft) = 66 ft
f is the coefficient of friction determined by the material the car was skidding on.
Coefficient of friction for wet concrete is 0.65
V = √32*fd
V = √32 *0.65* 66
V = 242.679 ft/s ≅ 243 ft/s (nearest whole number)
If a car skids 66 ft on wet concrete, it will move at 243 ft/s when the brake is applied.
Answer: 1.77 s
Explanation: In order to solve this problem we have to use the kinematic equation for the position, so we have:
xf= xo+vo*t+(g*t^2)/2 we can consider the origin on the top so the xo=0 and xf=29 m; then
(g*t^2)/2+vo*t-xf=0 vo is the initail velocity, vo=7.65 m/s
then by solving the quadratric equation in t
t=1.77 s
Answer:
The inlet velocity is 21.9 m/s.
The mass flow rate at reach exit is 1.7 kg/s.
Explanation:
Given that,
Mass flow rate = 2 kg/s
Diameter of inlet pipe = 5.2 cm
Fifteen percent of the flow leaves through location (2) and the remainder leaves at (3)
The mass flow rate is

We need to calculate the mass flow rate at reach exit
Using formula of mass



We need to calculate the inlet velocity
Using formula of velocity

Put the value into the formula


Hence, The inlet velocity is 21.9 m/s.
The mass flow rate at reach exit is 1.7 kg/s.
For any mass m:
a = F/m
v = √2*F/m*s = √2F/sm = k/√m
Momentum = mv = k√m
Energy = 1/ mv² = 1/2 m.k²/m = 1/2k²
SO
Both will have same energy
The larger mass will have greater momentum