Question

A 140 kg barrel that is initially at rest is pushed by a constant net force of 40N. The barrel travels 200cm in 5 s. The acceleration of the barrel is 0.25 m/s?. Calculate the increase in kinetic energy during the 5 s. 7. Two objects are hung from strings (figure). The top object (ml) has a mass of 15 kg and the bottom object(m2) has a mass of 10 kg. Calculate the tension in each string. [A-5] String A mi stringB ma Calculate the net force when each of the following sets of forces act on the same object. Draw it. Use x and y component method. [K-6] 52 N[N], 63 N [E],91 N [ 520 W]

Answer 1

Griver, the batt Set barree is really at rest. so moral verwity 0,20 Acceleration, as 0-2.5 ms cet the final speed de. be u The barre travels 200cm 2 m 5 S.. tras in او 앗 h - 0 + 2x0.25 mx 2 m ot MOD I mis. Mutial Kinetic energet, ker timas kimease energes, kaya mus=0 2 1 mer 2 s mass of barren. ma 190 * 8 KEJ = 2x 140 kg xh mys) Torty GKEG LEJ 16, -(70-0) N270 g irereone im Kinetic energy is 70J. 7) Free body heyrum A & TB TY2 YTB mig for mass me, I fnet 0 2) TB- myno ITB a g my for mass TA TB-mgco I fredo, Tarmigt To R mg two ma mag

(2) grow, m, s 15kg, mga 10fd, go go gmis. Tas (15+10) kg a sormir 17 = 2950 Tor 10kg x sof mis ITB2 98 m 9 52N S F-635 201 Fr FESINI diretton. 2 F tw maken so here, 7, 2520, acts on the object in thy so, flexo, Firgas2N. 2630, acts on objet an te dire sitn. 50 €2,8 = 63N, E2, y = 0. en aju or cy GX48 , y component of E Ez WS 2012-31 N X COS 20'<-85.512 N. x component of fz Fm, a X=-f3 573.2015 SINX Sir205-31-1236 N. x component, Ex af, x + F2 x + fix c10+63 – 31.4998902 3108762 Net y component, Fyn fy tfzy tf3y (52 +0-85. (3) so net 5.512N C-39.512 N.

so net force, fra ฟ J (31.8762)3(-99.612) fx fra 46.25 N. o f taar Qatarry (2) -33.5121 31.8762 acts below is f = 46.25 ~ so the ret force are 3 axes tooted twe horizonte or so-46 2490 from to the right) F = 46.256, 1514°] * [E46's]
in order to find the change in kinetic energy we have to find the velocity of the barrel at t = 5. Initially the barrell was rest. The kinetic energy = ½mv²