Other Physics Answers

The brick wall (of thermal conductivity 1 W/m · ◦ C) of a building has dimensions of 4.5 m by 4 m and is 19 cm thick. How much heat flows through the wall in a 6.4 h period when the average inside and outside temperatures are, respectively, 16◦C and 2◦C? Answer in units of MJ.

A 89.2 kg weight-watcher wishes to climb a mountain to work off the equivalent of a large piece of chocolate cake rated at 724 (food) Calories. How high must the person climb? The acceleration due to gravity is 9.8 m/s 2 and 1 food Calorie is 10^3 calories. Answer in units of km.

 If two pendulums each of mass 0.6 kg and length 1m are connected by a spring of force constant 0.3 

N/m, calculate the normal modes of frequencies for the coupled system.

A flywheel turns at 456 rpm. Compute the angular speed (in rad/s) at any point in the wheel.

   A long jumper is attempting to equal the world record of 8.95 metres.

(i) Determine the angle of take-off that would enable the long jumper to attain the maximum range.

(ii) Determine the velocity of take-off that would enable the long jumper to equal the world record.

(iii) Find the maximum height attained by the long jumper while equalling the world record.

(iv)Find the time the long jumper spends in the air.

1.     An object is projected is projected at an angle 0^o to the ground at a speed V m/s Neglecting the air resistance, show that the range of the projectile is

R=V^2 sin20/g

A uniform bar 3.00 m long is held by ropes at the ends making angle 60.0 degrees and 30.0 degrees, respectively, with the horizontal. A weight of 200 N is hung 0.500 m from the left end where the 60.0 degrees rope is attached. Find the tension in the ropes (T1 & T2) and the weight (W) of the bar. (Hint: Formulate three equations for the three unknowns, 2 equations for the 1st condition and 1 equation for the 2nd condition.)

A 50.0-N body is supported by two ropes, one making 30.0 degrees with the vertical and another making 45.0 degrees with the horizontal as shown in the figure below. What is the tension in the ropes?

A uniform bar 3.00 m long is held by ropes at the ends making angle 60.0 and 30.0, respectively, with the horizontal. A weight of 200 N is hung 0.500 m from the left end where the 60.0 rope is attached. Find the tension in the ropes (T1 & T2) and the weight (W) of the bar. (Hint: Formulate three equations for the three unknowns, 2 equations for the 1st condition and 1 equation for the 2nd condition.)

A body is falling through water with its terminal velocity. Find the visco force when its volume is 50cm^3 and specific gravity is 1.4.