1.an engine develops 65kW over a period of 20minutes. The engine uses 5kg of petrol.

Calculate the following:-

A. The heat gegenerated
B. The power generated by the petrol
C. The efficiency Of the engine

2.A square steel plate with sides of 12cm long, is heated and the change in area is 1.723mm^2.determine the change in temperature

3.steam is generated in a boiler at pressure of 0.1MPa. Calculate the enthalpy required for 1kg of steam when the dryness factor is 0.96

4.a hydraulic press lifts a body of 2 tons. The diameter of the ram is twice the diameter of the plunger. Determine the effort force exerted by the plunger.

5. A force of 400N is exerted on the plunger of a hydraulic press. The diameter of the plunger is 400mm and the stroke length is 120cm. Calculate the following:

A.pressure exerted by the plunger.
B.volume delivered per stroke
C.work done after 10 pumping strokes of the plunger

1. To calculate the requested values in this problem, we will use some basic formulas from physics.

A. The heat generated can be calculated using the formula Q = P * t, where Q is the heat, P is the power, and t is the time. In this case, the power is given as 65kW and the time is 20 minutes. First, convert the time to hours since the power is given in kilowatts. 20 minutes = 20/60 = 1/3 hour. Now plug the values into the formula: Q = (65kW)*(1/3h) = 21.67 kWh.

B. The power generated by the petrol can be calculated by dividing the heat generated (Q) by the mass of petrol (m). The heat generated was calculated in part A and given as 21.67 kWh. The mass of the petrol is given as 5 kg. Convert the heat to joules since the mass of petrol is given in kilograms. 1 kWh = 3.6 * 10^6 J. So, 21.67 kWh = 21.67 * 3.6 * 10^6 J. Now divide this by the mass of the petrol: Power = (21.67 * 3.6 * 10^6 J) / 5 kg.

C. The efficiency of the engine can be calculated using the formula Efficiency = (Useful Energy Output / Energy Input) * 100%. The useful energy output in this case is the power generated by the petrol, which was calculated in part B. The energy input is the heat generated, which was calculated in part A.

2. To calculate the change in temperature in this problem, we need to use the formula for linear thermal expansion. The formula is given by: ΔA = α * A * ΔT, where ΔA is the change in area, α is the coefficient of linear expansion, A is the original area, and ΔT is the change in temperature. In this case, ΔA is given as 1.723 mm^2, A is given as (12 cm)^2, and α is a known value for steel. Calculate ΔT as follows: ΔT = (ΔA) / (α * A).

3. To calculate the enthalpy required for 1kg of steam, we need to use the steam tables. These tables provide data such as pressure, temperature, specific volume, and enthalpy for different states of steam. Find the specific volume (v) and enthalpy (h) values for 0.1MPa and a dryness factor of 0.96. Multiply the specific volume by the dryness factor to get the volume of the dry steam, and then multiply the enthalpy by the dryness factor to get the enthalpy of the dry steam.

4. To determine the effort force exerted by the plunger in a hydraulic press, we need to use Pascal's law, which states that the pressure in a confined fluid is transmitted uniformly in all directions. The ratio of the areas of the plunger to the ram is equal to the ratio of the effort force to the load. Since the diameter of the ram is twice the diameter of the plunger, the ratio of their areas is 1:4. Therefore, the effort force can be calculated by multiplying the load force by this ratio.

5. To calculate the requested values in this problem, we'll need to use some basic formulas for pressure, volume, and work done.

A. The pressure exerted by the plunger can be calculated using the formula P = F / A, where P is the pressure, F is the force, and A is the area. In this case, the force is given as 400N and the diameter of the plunger is given as 400mm. First, convert the diameter to meters by dividing by 1000. Then calculate the area of the plunger using the formula A = π * (r^2), where r is the radius. Finally, divide the force by the area to get the pressure.

B. The volume delivered per stroke can be calculated using the formula V = A * h, where V is the volume, A is the area, and h is the stroke length. The area of the plunger was calculated in part A, and the stroke length is given as 120cm. Convert the stroke length to meters before plugging it into the formula.

C. The work done after 10 pumping strokes of the plunger can be calculated using the formula W = F * d, where W is the work, F is the force, and d is the distance. In this case, the force is given as 400 N, and the distance is calculated by multiplying the stroke length by the number of strokes.