Multiple Choice Questions on Free Fall:
- Free fall acceleration is the acceleration that all bodies acquire in free fall near the surface of the Earth, regardless of their mass.
- Denoted by the letter g.
- The free-fall acceleration on Earth is approximately equal to g = 9.81 m/s2.
- Free fall is uniformly accelerated motion.
- The acceleration of free fall in a simplified form can be calculated by the formula g u003d F m, which is obtained from the formula F u003d m ⋅ g, where F is the force of gravity or the weight of the body at rest or uniform rectilinear motion, m is the mass of the body that the planet attracts, g is the free-fall acceleration.
- Experiments showed that the speed and acceleration of free fall of bodies to the ground depend on the mass of the body – a body of greater mass (and weight) has a greater acceleration than a body of less mass
1. A small ball falls freely from a height, the kinetic energy of the ball in the process of falling______
A. proportional to the distance it fell
B. proportional to the square of its falling distance
C. proportional to the square of the time it moves
D. Both A and C
2. Two objects of different masses falling freely near the surface of the moon would
A. have the same velocities at any instant
B. have different acceleration
C. experiences forces of the same magnitude
D. undergo a change in their inertia
3. An object is in free-fall motion, taking g=10m/s 2, then the size of the object’s velocity at the end of the 5th s is________
A. 25 m/s
B. 50 m/s
C. 100 m/s
D. 125 m/s
4. A stone is in free fall from the edge of the balcony of the building. Divide the total time of its movement in the air into three equal sections, if its displacement in the first period is 1.2m, then its displacement in the third period is_______
5. Which of the following statements about free fall is true
A. It is v 0 =0, a=g, vertical downward uniform acceleration linear motion
b. The ratio of displacements passed within the first three consecutive 1s is 1:4:9
c. At the beginning of three consecutive 1s, the ratio of the speed and size is 1:2:3
D. Both A and C
6. After the free-fall time t of object A from a height, object B falls freely from the same position. Before both A and B fall to the ground, taking A as the reference object, the motion state of the B object is:
A. relatively static
B. straight line up
C. downward motion in a straight line
D. straight up
7. Two students are at different heights of the tower, using two balls with different weights to do free-fall motion experiments. It is known that the gravity of ball A is twice that of ball B, and the height at which ball A is released is twice the height at which ball B is released. times, ignoring air resistance, then_______
A. The accelerations of the falling balls A and B are equal
b. The acceleration of ball A falling is twice that of ball B
C. Balls A and B each fall at the same speed for 1 s
D. Both A and C
8. In the following motion, the acceleration change is_________
A. flat throw
B. oblique throwing movement
C. free fall
D. uniform circular motion
9. Which of the following statements about free fall is true_______
A. The vertical downward motion of an object in free fall.
B. A motion whose acceleration is equal to the acceleration of gravity is a free-fall motion.
C. In the process of free fall, objects of different masses change in the same law.
D. The object is in free fall, and the force has nothing to do with the mass
10. An object is in free fall from a height of 45m from the ground (g is 10m/s 2 ), which of the following options is correct_______
A. The object lands after moving for 3s
b. The speed of the object when it hits the ground is 30m/s
c. The displacement of the object in the last 1s before landing is 25m
D. All of these
11. Which of the following is true about the acceleration of a free-falling body?
A. Heavy objects fall with high acceleration
B. The acceleration of light and heavy objects falling at the same place is the same
C. This acceleration is greater at the earth’s equator than at the earth’s north pole
D. This acceleration is the same everywhere on earth