Bulletproof jacket में गोली क्यों नहीं लगती?How bulletproof jacket works? #shorts

A steam cylindrical pipe of radius 5 cm carries steam at 100^@C . The pipe is covered by a jacket of insulating material 2 cm thick having a thermal conductivity 0.07 W//m-K . If the temperature at the outer wall of the pipe jacket is 20^@C , how much heat is lost through the jacket per metre length in an hours? .

A steam pipe of radius 5cm carries steam at 100^(@)C The pipe is covered by a jacket of insulating material 2cm thick having a ther mal conductivity 0.07Wm^(-1) k^(-1) if the tempera ture at the outer wall of the pipe jacket is 20^(@)C how much heat is lost through the jacket per mater lenght in an hour ? .

If 30 persons take 10 days to complete a certain work working 8 hours a day. Then 40 persons should work how many hours a day so that the work is completed in 6 days? यदि 30 लोग प्रतिदिन 8 घंटे कार्य करके किसी कार्य को 10 दिनों में पूरा करते हैं, तो इस कार्य को 6 दिनों में पूरा करने के लिए 40 व्यक्ति दिन में कितने घंटे कार्य करेंगे ?