1231. A boy walks 6 kilometers to his school at a constant speed of 2.5 kilometers per hour and walks back the same speed of 5 kilometers per hour. His average speed for the round trip, expressed in kilometers per hour, is:

A. 24/13
B. 10/3 *
C. 3
D. 4.8

1232. When an airplane is flying horizontally at 600 km/h at a height of 1960 meters, it can drop a bomb when it is vertically above point A on the ground.Point B is where the bomb lands on the ground. . The stomach muscle’s distance:

A. 1200 M
B. 0.33 KM
C. 3.33 KM *
D. 33 KM

1233. A car travels 60 kilometers in total, half of the time at 80 kilometers per hour and the other half at 40 kilometers per hour. What is the typical speed of the vehicle ?

A. 60 Km/hr *
B. 80 Km/hr
C. 120 Km/hr
D. 180 Km/hr

1234. Elastically, a ball of mass m traveling at the same speed collides with another ball that is stationary. The occurrence ball will lose most extreme motor energy when mass of the fixed ball is :

A. m *
B. 2 m
C. 4 m
D. Infinity

1235. A 120-meter-long train travels at a speed of 20 m/s in the direction of a path. A 130-meter-long train B traveling in the opposite direction at 30 M/s crosses the primary train within the following time frame:

A. 6 s
B. 36 s
C. 38 s
D. None of these *

1236. Which velocity can a ball be projected vertically at such that its fifth-second distance is twice that of its sixth-second distance (g=10m/s2)?

A. 58.8 m/s
B. 49m/ s
C. 65 m/s *
D. 19.6 m/s

1237. A ball bounces 2.5 meters after falling 10 meters from height onto the surface. The average acceleration during contact is as follows if the duration of contact with the floor is 0.01 seconds:

A. 2100 m/s2 *
B. 1400 m/s2
C. 1200 m/s2
D. 1100 m/s2

1238. In 20 seconds, a car at rest can accelerate uniformly to 144 km/h, covering the following distance:

A. 20 m
B. 400 m *
C. 1440 m
D. 2880 m

1239. A 120-kg vehicle travels at a uniform speed of 108 kilometers per hour. The force required to bring the vehicle to a stop in 10 seconds is:

A. 120 * 10.8 N
B. 180 N
C. 720 N
D. 360 N *

1240. A passenger in a lift drops a coin as the lift descends at the same speed. The coin’s acceleration toward the ground will be:

A. Zero
B. g *
C. -g
D. v+g