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Questions : 7, 8 and 9
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Kumar Ketan is teaching live on Unacademy Plus

Kumar Ketan
#Specialisation in Electronics #6 years teaching experience #Physics Faculty in Kota #"magical education" (211k+ subs) #Writer

Unacademy user
do Shi hogye sir 1 or 3 higya 2sra m psedu force tak Dimag nhi phaucha lekin answer ahgya tha lekin Mene isse count nhi Kiya
2 correct and 1 incorrect .

  1. unacademy 62.9k views 4.8 Kumar Ketan Follow me on the Unacademy #15 Educator in IIT JEE #6 years teaching experience #IIT JEE Physics #YouTuber 'magical education" (170k+ subs) #Unacademy educator (60k+ lifetin eviews) 3k 2 37 Followers Following Courses Get updates about new courses . Watch all my lessons . Download slides and watch offline Message Lists (1) Kumar Ketan HINDI IT JEE Physics by Kumar Ketan for IT JEE 52 saves Kumar Ketan

  2. Themaximum wavelength ofradiation that can produce photoelectric effect in certain metal is 200nm. Themaximumkineticenergyacquired by electron due to radiation of wavelength 100 nm will be (a) 12.4 eV (c) 100 eV (b) 6.2 eV (d) 200 eV

  3. Here, = 200 nm, = 100 nm, hc --= 1240 eV nm hc hc Maximum kinetic energy (in eV) hc (1 1 = 1 240 =6.2eV 100 200

  4. A block of mass m is in contact with the cart C as shown in the figure. The coefficient of static friction between the block and the cart is . The acceleration of the cart that will prevent the block from falling satisfies (a) >mg. (b) > (c) & (d) <&

  5. - "Pseudo acceleration mg Pseudo force or fictitious force, F i.-m1 From Free body diagram Force of friction, f- m The block of mass m will not fall as long as fe mg

  6. If an average person jogs, he produces 14.5 x 103 cal per minute. This is removed by the evaporation of sweat. The amount of sweat evaporated per minute (assuming 1 kg requires 580 103 cal for evaporation) is (a) 0.025 kg (c) 0.05 kg (b) 2.25 kg (d) 0.20 kg

  7. Energy produces - 14.5 x 103 cal min-1 14.5 x 103 cal min-0.025 kg 580 x 103 cal kg1 Amount of sweat evaporated per min