Colliding Objects
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4th Grade Science › Colliding Objects
Glen and his friend London are going sledding at a local park. There are two hills to choose from, "The Bunny Slopes," which are small hills and lots of flat surfaces, and "The Dragon," which is a steep hill and not for beginners. If London goes first and reaches the bottom and Glen crashes into him from behind on "The Dragon," what would happen to the motion of their sleds?
Glen's sled would slow down or stop on impact, and London's sled would move forward.
Glen's sled would move forward on impact, and London's sled would stop.
Glen's sled would speed up on impact, and London's sled would move forward.
Glen's sled would speed up on impact, and London's sled would stop.
Explanation
If London is waiting at the bottom of the hill and Glen crashes into him there will be a change in the energy transferred when the collision takes place. When Glen hits the back of London his sled will stop or slow down while London's sled will be pushed forward and move. There is a transfer of energy from Glen to London that takes place when any two objects collide.
The diagrams below show a force on an object and its motion.
Which diagram correctly shows the relationship between the force and the motion?
Diagram A
Diagram B
Diagram C
Diagram D
Explanation
The diagram that correctly depicts the relationship between force and motion is Diagram B. The force of an object is colliding with the white sphere and pushing it forward. The sphere will move in the direction it is being pushed. If two objects collide, energy will be transferred between both, and there will be a change in motion.
Glen and his friend London are going sledding at a local park. There are two hills to choose from, "The Bunny Slopes," which are small hills and lots of flat surfaces, and "The Dragon," which is a steep hill and not for beginners. If London goes first and reaches the bottom and Glen crashes into him from behind on "The Dragon," what would happen to the motion of their sleds?
Glen's sled would slow down or stop on impact, and London's sled would move forward.
Glen's sled would move forward on impact, and London's sled would stop.
Glen's sled would speed up on impact, and London's sled would move forward.
Glen's sled would speed up on impact, and London's sled would stop.
Explanation
If London is waiting at the bottom of the hill and Glen crashes into him there will be a change in the energy transferred when the collision takes place. When Glen hits the back of London his sled will stop or slow down while London's sled will be pushed forward and move. There is a transfer of energy from Glen to London that takes place when any two objects collide.
The diagrams below show a force on an object and its motion.
Which diagram correctly shows the relationship between the force and the motion?
Diagram A
Diagram B
Diagram C
Diagram D
Explanation
The diagram that correctly depicts the relationship between force and motion is Diagram B. The force of an object is colliding with the white sphere and pushing it forward. The sphere will move in the direction it is being pushed. If two objects collide, energy will be transferred between both, and there will be a change in motion.
In the image below, the arrows depict energy being applied to a triangle. This energy would cause the triangle to change positions. What is another name for a change in position?
Location
Motion
Ovation
Deflation
Explanation
Another name for a change in position is "motion." Motion is the process or action of being moved or moving. The arrows are pushing against the triangle, and it will move in the direction of the energy being transferred.
Karyssa is bowling with her friends, and she is looking at the pins when they each throw the ball. Looking at the pictures of the pins, Karyssa has to make a prediction of which ball she thinks had a greater speed upon collision and why?
In the first picture, the ball has a higher speed because the ball appears to be moving faster, and the pins are falling.
In the second picture, the ball has a higher speed because the pins are flying into the air, and more are falling.
In the first picture, the ball has a higher speed because the pins are falling sideways.
In the second picture, the ball has a higher speed because the player has a proper stance and looks strong.
Explanation
Both of these photos represent changes in energy during a collision. The ball is transferring energy to the pins when they make contact. Karyssa could predict based on the pictures and the positions of the pins, which she believed had a higher speed upon collision. When examining the photos, they both show pins falling and the ball making contact with the pins. The second photo shows the pins almost exploding at the end of the lane and flying through the air. A reasonable prediction could be made that this ball had higher speed upon collision because there was more energy transferred to the pins, and there was a more significant "reaction" when the crash took place.
In the image below, the arrows depict energy being applied to a triangle. This energy would cause the triangle to change positions. What is another name for a change in position?
Location
Motion
Ovation
Deflation
Explanation
Another name for a change in position is "motion." Motion is the process or action of being moved or moving. The arrows are pushing against the triangle, and it will move in the direction of the energy being transferred.
Karyssa is bowling with her friends, and she is looking at the pins when they each throw the ball. Looking at the pictures of the pins, Karyssa has to make a prediction of which ball she thinks had a greater speed upon collision and why?
In the first picture, the ball has a higher speed because the ball appears to be moving faster, and the pins are falling.
In the second picture, the ball has a higher speed because the pins are flying into the air, and more are falling.
In the first picture, the ball has a higher speed because the pins are falling sideways.
In the second picture, the ball has a higher speed because the player has a proper stance and looks strong.
Explanation
Both of these photos represent changes in energy during a collision. The ball is transferring energy to the pins when they make contact. Karyssa could predict based on the pictures and the positions of the pins, which she believed had a higher speed upon collision. When examining the photos, they both show pins falling and the ball making contact with the pins. The second photo shows the pins almost exploding at the end of the lane and flying through the air. A reasonable prediction could be made that this ball had higher speed upon collision because there was more energy transferred to the pins, and there was a more significant "reaction" when the crash took place.
When objects collide, the contact forces transfer energy so as to change the object's motions.
True
False
Explanation
The statement presented in the question is correct. If two objects collide, energy will be transferred between both, and there will be a change in motion. If I were to run into a friend at recess, we would both slow down and possibly fall backward or sideways due to the force of the impact. Objects can change speed, direction, or come to a complete stop because of a transfer of energy during a collision.
Two students are rolling a ball back and forth across the playground grass. Suddenly, the ball changes direction. When the students explore why this happened, they see that the ball hit a rock.
Which of these caused the ball to change direction?
A change in mass
A change in force
A change in volume
A change in gravity
Explanation
In this situation, the ball changed direction because it collided with the rock, and there was a change in force. If two objects collide, energy will be transferred between both, and there will be a change in motion. Objects can change speed, direction, or come to a complete stop because of a transfer of energy during a collision.