The correct answer is A. In the direction of applied force. This is because acceleration occurs n the direction of applied force according to Newtons second law of motion which states that the acceleration of a body is directly proportional to the applied force and takes place in the direction of force.
B. third
for every action there is a reaction*
Answer:
(a). 14.4 lbf/in^2.
(b). 27.8 in, AS THE TEMPERATURE INCREASES, THE LENGTH OF MERCURY DECREASES.
Explanation:
So, from the question above we are given the following parameters which are going to help us in solving this particular Question;
=> The "barometer accidentally contains 6.5 inches of water on top of the mercury column (so there is also water vapor instead of a vacuum at the top of the barometer)"
=> "On a day when the temperature is 70oF, the mercury column height is 28.35 inches (corrected for thermal expansion)."
With these knowledge, let us delve right into the solution;
(a). The barometric pressure = water vapor pressure + acceleration due to gravity (ft/s^2) × water density(slug/ft^3) × {ft/12 in}^3 × [ height of mercury column + specific gravity of mercury × height of water column].
The barometric pressure= 0.363 + {(62.146) ÷ (12^3) × 390.6425}. = 14.4 lbf/in^2.
(b). { (13.55 × length of mercury) + 6.5 } × (62.15÷ 12^3) = 14.4 - 0.603.
Length of mercury = 27.8 in.
AS THE TEMPERATURE INCREASES, THE LENGTH OF MERCURY DECREASES.
Answer:
- 210 rad/s²
Explanation:
n = frequency of rotation = 3400/60 = 170/3 per sec.
angular velocity ω ( 0 ) at time 0 = 2π n = 2π x 170/3
angular velocity at time t = ω(t) = 0
now, ω²( t) = w²(o) + 2α Φ ( α = angular acceleration and Φ = angular displacement) = 2π x 48 rad.
0 = ( 2π x 170/3 )² + 2α x 48 x 2π
α = - (2π x 170 x 170 )/ (3 x 3 x 2 x 48 ) = 210 rad / s²
Explanation:
1.) Work = Force*Distance
2.) The direction of motion lies in the same direction as the tension in the cable. So the work done by tension would be positive.
3.) The direction of the weight (due to gravity) would act opposite to the direction of motion of the elevator, so work done by gravity becomes negative.