1. You and your bike have a combined mass of 80 kg. How much braking force has to be applied to slow you from a velocity of 5 m/s to a complete stop in 2 s? a 5} v t f f 2 2 v t i}i 5 5 2.5 m/s 2 F 5 ma 5 80 kg 3 (22.5 m/s 2) 5 2 200 N 2. Before opening his parachute, a sky diver with a mass of 90.0 kg experiences an upward force from air

7 A uniform plank rests on a pivot at its centre. Two children P and Q sit on the plank in the positions shown. child P child Q pivot 1.2 m 1.5 m The mass of child P is 25 kg. The plank is balanced. What is the mass of child Q? A 20 kg B 25 kg C 31 kg D 45 kg 8 The diagram shows three forces acting on an object. 6 N 1 N 9 N

Problem 215 A uniform concrete slab of total weight W is to be attached, as shown in Fig. P-215, to two rods whose lower ends are on the same level. Determine the ratio of the areas of the rods so that the slab will remain level. If the unit mass of steel is 7850 kg/m 3 and E = 200 × 10 3 MN/ m 2, find the total . elongation of the rod

that the volume of the system is fixed (so that no work is transferred) and it's mass is constant, energy conservation is simply described by dE dt = Q˙ (1.1) in which Q˙ is the rate of heat transfer into the system and Eis the energy of the system. If the system is not in equilibrium then Ecannot be related to a single temperature of the

4–59 Chickens with an average mass of 1.7 kg (k 0.45 W/m · °C and 0.13 10 6 m2/s) initially at a uniform temperature of 15°C are to be chilled in agitated brine at 10°C. The average heat transfer coefficient between the chicken and the brine is determined experimentally to be 440W/m2 · °C.

11.50) You pull downward with a force of 35 N on a rope that passes over a disk-shaped pulley of mass 1.5 kg and radius 0.075 m. The other end of the rope is attached to a 0.87 kg mass. This is the same problem as 11.49. The answer for the acceleration is above. 11.54) A 0.015 kg record with a radius of 15 cm rotates with an angular speed of

There is agap D ¼ 0:18 mm between the middle bar, which is made of aluminum, and the slab.Neglecting the mass of the slab, calculate the stress in each rod when the temperaturein the assembly is increased by 85 C. Use the following data:Each copper rod A (mm2) a (/ C) E (GPa)Aluminum rod 500 16:8 Â 10À6 120 400 23:1 Â 10À6 702.83 A bronze

The equation relating thermal energy to thermal mass is: = where Q is the thermal energy transferred, C th is the thermal mass of the body, and ΔT is the change in temperature.. For example, if 250 J of heat energy is added to a copper gear with a thermal mass of 38.46 J/°C, its temperature will rise by 6.50 °C.

A container of water has been outdoors in cold weather until a 5.0 cm-thick slab of ice has formed on its surface. The air above the ice is at -10 ¡ C. Calculate the rate of formation of ice (in centimeters per hour) on the bottom surface of the ice slab. Take the thermal conductivity of ice to be 0.0040 cal/s . cm .

Reading time: 1 minute A cantilever beam is a rigid structural element supported at one end and free at the other, as shown in Figure-1. The cantilever beam can be either made of concrete or steel whose one end is cast or anchored to a vertical support. It is a horizontal beam structure whose []

SLAB DESIGN Reading Assignment Chapter 9 of Text and, Chapter 13 of ACI318-02 Introduction ACI318 Code provides two design procedures for slab systems: 13.6.1 Direct Design Method (DDM) For slab systems with or without beams loaded only by gravity loads and having a fairly regular layout meeting the following conditions:

4. Pretexture the slab perimeterPretexture along the perimeter edges of the slab about 6 to 12 inches inward with a texturing skin or flex mat. This step is important because when you're working with a nonflexible stamp, the tool will overlap the edge of the form and you won’t be able to fully depress it into the concrete surface.

wall that is restrained at the bottom by a slab and at the top by a floor framing system prior to placing soil backfill against the wall. The active pressure develops when the wall is free to move outward such as a typical retaining wall and the soil mass stretches sufficiently to mobilize its shear strength.

A spring with a k = 15.3 N/m hangs 3.5 cm above a tabletop when a 400 g mass is hung from it. If the mass A cylindrical aluminum pillar 7.00 high has a radius of 30.0 cm. If a 2000-kg sculpture is placed on top of the pillar, by how much is the pillar compressed? A uniform pressure of 5.00 × 104 Pa is exerted on a copper block having a

A round wastepaper basket with a 0.15 m radius opening is in a uniform electric field of 300 N/C, perpendicular to the opening. The total flux through the sides and bottom, in N ·m2/C, is: (1) - 21 (2) 4.2 (3) 0 (4) 280 (5) can't tell without knowing the areas of the sides and bottom Solution

The density of pure water is also 62.4 lbs/cu.ft (pounds per cubic foot) and if we know that a sample of ammonium nitrate has a sg of 0.73 then we can calculate that its density is 0.73 x 62.4 = 45.552 lbs/cu.ft. As general information, kg/cu.m divided by 16.01846 = lbs/cu.ft.