A particle moves 70 m west, then moves 120 m east, and finally moves east again

Question

A particle moves 70 m west, then moves 120 m east, and finally moves east again a distance of 90 m. If ea is chosen as the positive direction, what is the particle's resultant displacement? 40 m -40 m 280 m 140 m A particle moves 20 m east in 10 s and then returns to its starting point taking an additional 30 s. If east is chosen as the positive direction, what is the average speed of the particle? 0.50 m/s -0.50 m/s 2.66 m/s 1.0 m/s A ball is pushed with an initial velocity of 4.0 m/s. The ball rolls down a hill with a constant acceleration 1.5 m/s^2. The ball reaches the bottom of the hill in 8.0 s. What is the ball's velocity at the bottom of the hi 10 m/s 12 m/s 16 m/s 17 m/s A bird, accelerating from rest at a constant rate, experiences a displacement of 28 m in 4 s. What is the fi velocity after 4 s? 1.8 m/s 3.5 m/s 14 m/s zero A drag racer starts from rest and accelerates at 18 m/s^2 for the entire distance of 400 m (approximately, mile). What is the velocity of the race car at the end of the run? 45 m/s 89 m/s 120 m/s 180 m/s If the displacement of an object is given in SI units by delta x = -12t + 2t^2, at t = 2 s its velocity and are, respectively: positive, positive positive, negative negative, negative negative, positive A rock is thrown straight up with an initial velocity of 14.0 m/s. What maximum height will the rock before starting to fall downward? (Take g equal to 9.80 m/s^2.) 14.3 m 10.0 m

Explanation / Answer

1) d1 = -70 m i, d2 = 120 i m, d3 = 90 i m

d = d1+d2+d3

d = -70+120+90

d = 140 m

Correct option is (d)

2) d1 = 20 i m ,d2 = -20 i m, t1 = 10 s, t2 = 30s

average speed = total speed/total time

= (20+20)/(10+30) = 1 m/s

Correct option is (d)

3) u = 4 m/s, a = 1.5 m/s^2, t = 8 s

v = u +at

v = 4 +1.5*8

v = 16 m/s

correct option is (c)

4) s = 28 m , t = 4s, u= 0

s = ut+(1/2)at^2

28 = 0 +0.5*a*4^2

a = 3.5 m/s^2

v^2 -u^2 = 2as

v^2 -0 = 2*3.5*28

v = 14 m/s

correct option is (c)

5) a = 18 m/s^2, s = 400 m

v^2-u^2 = 2as

v^2 -0 = 2*18*400

v= 120 m/s

correct option is (c)

6) Dx = -12t +2t^2, t = 2s

v =Dx/Dt = -12 +4t

v = -12+8 = -4 m/s

a = Dv/Dt = 4

correct option is (d)

7) u = 14 m/s,

H = u^2/2g

H = 14*14/(2*9.8)

H = 10 m

correct option is (b)

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.