Title 2. W.P.E. (Pass.Q.) E.pdf ✅

PHYSICS Passage # 1 (Ques. 1 to 3) A force of 0.5 N is applied on upper block as shown in diagram. Displacement of upper block is 3 m. 1 kg 2 kg  = 0.1  = 0 F = 0.5 N Sol. a = M m F + = 6 1 m/s2 1kg will not slide w.r.t. lower block because Ma < mg 1 kg 2 kg  = 0.1  = 0 F = 0.5 N Q.1 The work done by lower block on upper block is - (A) 1 J (B) –1 J (C) 2 J (D) – 2 J [B] Sol. Friction force on upper block due to lower block is opposite to the motion and it is, f = ma = 2 × 1/6 = 1/3 N  W = –f .S = – 1/3 × 3 =–1 J Q.2 The work done by lower block on upper block in the frame of lower block is - (A) –1 J (B) –2 J (C) 2 J (D) zero [D] Sol.  Upper block is stationary w.r.t. lower block  W = 0 Q.3 The work done by upper block on lower block is - (A) 1 J (B) –1 J (C) – 2 J (D) 2 J [A] Sol.  Friction force on lower block due to upper block is in forward direction, f = Ma = 1/3 N  W = f .S = 1 J Passage # 2 (Ques. 4 & 5) A ball is released from point A as shown in figure. The ball leaves the track at B. All surfaces are smooth. B A ` 2 m 6 m Q.4 Let h be the maximum height from ground reached by ball after leaving track at B. then : (A) h = 6m (B) h < 6m (C) h > 6m (D) speed of the ball B will change if shape of track is changed keeping hA and hB constant Sol. [B] Q.5 If track makes an angle 30o with horizontal at B then maximum height attained by ball will be- (A) 3m (B) 4m (C) 4.5 m (D) 5m Sol. [A] Passage # 3 (Ques. 6 &7) The system is released from rest with both the springs in unstretched positions. Mass of each block is 1 kg and force constant of each spring is 10 N/m. Q.6 Extension of horizontal spring in equilibrium is- (A) 0.2 m (B) 0.4 m (C) 0.6 m (D) 0.8 m Sol. [B] Q.7 Maximum speed of the block placed horizontally is- (A) 3.21 m/s (B) 2.21 m/s (C) 1.93 m/s (D) 1.26 m/s Sol. [C] Passage # 4 (Ques. 8 & 9)


energy is multiplied by (1.2) 2 = 1.44, which is an increase of 44%. Q.21 Scott drives a very large 50s style car, and Laura drives a small 90s style car, so that every linear dimension of Scott's car is double that of Laura's car. On the basis of energy loss due to air resistance alone, how much more energy would you expect Scott's car to expend getting from Tucson to Phoenix than Laura's car? (A) Twice as much as energy (B) Four times as much energy (C) Eight times as much energy (D) Sixteen times as much energy Sol.[B] Comparing Scott’s car to Laura’s, all the linear dimensions are increased by a factor of 2 (see figure). The cross–sectional area A is width times height (A = hw), so if both h and w increase by factor of 2, then A increases by a factor of 4. Thus the required energy increases by a factor of 4, the increase in length does not matter. A1 A2 h  w