Explosions - Law Enforcement
The Explosions - Law Enforcement Concept Builder is comprised of a bank of 18 questions that are delivered to the learner across three different difficulty levels. All three difficulty levels use the same 18 questions. They are only different in terms of the number of questions that must be answered at each level. Questions are grouped and chosen at random from within the same group. If a learner misses a question within Question Group 1, then another question within the same group will be presented to the learner at a later time.
The three difficulty levels in this Concept Builder are differentiated as follows:
- Apprentice: 3 Question Groups (with 6 questions each)
- Masters: 6 Question Groups (with 3 questions each)
- Wizard: 9 Question Groups (with 2 questions each)
The questions and images used in this Concept Builder are shown below. Teachers are encouraged to view the questions in order to judge which activity is most appropriate for their classes.
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Law Enforcement - Explosions
Question 1
Two spring-loaded carts are at rest on a low-friction track. The spring is released, pushing the carts away from each other. Three situations are shown. Identify any situation that violates the law of momentum conservation.
NOTE: The bricks on top of the carts have the same mass as the cart. The arrows represent the velocity of the cart.

Question 2
Two spring-loaded carts are at rest on a low-friction track. The spring is released, pushing the carts away from each other. Three situations are shown. Identify any situation that violates the law of momentum conservation.
NOTE: The bricks on top of the carts have the same mass as the cart. The arrows represent the velocity of the cart.

Question 3
Two spring-loaded carts are at rest on a low-friction track. The spring is released, pushing the carts away from each other. Three situations are shown. Identify any situation that violates the law of momentum conservation. NOTE: The bricks on top of the carts have the same mass as the cart. The arrows represent the velocity of the cart.
Question 4
Two spring-loaded carts are at rest on a low-friction track. The spring is released, pushing the carts away from each other. Three situations are shown. Identify any situation that violates the law of momentum conservation.
NOTE: The bricks on top of the carts have the same mass as the cart. The arrows represent the velocity of the cart.
Question 5
Two spring-loaded carts are at rest on a low-friction track. The spring is released, pushing the carts away from each other. Three situations are shown. Identify any situation that violates the law of momentum conservation. NOTE: The bricks on top of the carts have the same mass as the cart. The arrows represent the velocity of the cart.
Question 6
Two spring-loaded carts are at rest on a low-friction track. The spring is released, pushing the carts away from each other. Three situations are shown. Identify any situation that violates the law of momentum conservation.
NOTE: The bricks on top of the carts have the same mass as the cart. The arrows represent the velocity of the cart.
Question 7
Two spring-loaded carts are at rest on a low-friction track. The spring is released, pushing the carts away from each other. Three situations are shown. Identify any situation that violates the law of momentum conservation.
NOTE: The bricks on top of the carts have the same mass as the cart. The arrows represent the velocity of the cart.
Question 8
Two spring-loaded carts are at rest on a low-friction track. The spring is released, pushing the carts away from each other. Three situations are shown. Identify any situation that violates the law of momentum conservation.
NOTE: The bricks on top of the carts have the same mass as the cart. The arrows represent the velocity of the cart.
Question 9
Two spring-loaded carts are at rest on a low-friction track. The spring is released, pushing the carts away from each other. Three situations are shown. Identify any situation that violates the law of momentum conservation.
NOTE: The bricks on top of the carts have the same mass as the cart. The arrows represent the velocity of the cart.
Question 10
Two spring-loaded carts are at rest on a low-friction track. The spring is released, pushing the carts away from each other. Three situations are shown. Identify any situation that violates the law of momentum conservation. NOTE: The bricks on top of the carts have the same mass as the cart. The arrows represent the velocity of the cart.
Question 11
Two spring-loaded carts are at rest on a low-friction track. The spring is released, pushing the carts away from each other. Three situations are shown. Identify any situation that violates the law of momentum conservation. NOTE: The bricks on top of the carts have the same mass as the cart. The arrows represent the velocity of the cart.
Question 12
Two spring-loaded carts are at rest on a low-friction track. The spring is released, pushing the carts away from each other. Three situations are shown. Identify any situation that violates the law of momentum conservation. NOTE: The bricks on top of the carts have the same mass as the cart. The arrows represent the velocity of the cart.
Question 13
Two spring-loaded carts are at rest on a low-friction track. The spring is released, pushing the carts away from each other. Three situations are shown. Identify any situation that violates the law of momentum conservation. NOTE: The bricks on top of the carts have the same mass as the cart. The arrows represent the velocity of the cart.
Question 14
Two spring-loaded carts are at rest on a low-friction track. The spring is released, pushing the carts away from each other. Three situations are shown. Identify any situation that violates the law of momentum conservation. NOTE: The bricks on top of the carts have the same mass as the cart. The arrows represent the velocity of the cart.
Question 15
Two spring-loaded carts are at rest on a low-friction track. The spring is released, pushing the carts away from each other. Three situations are shown. Identify any situation that violates the law of momentum conservation. NOTE: The bricks on top of the carts have the same mass as the cart. The arrows represent the velocity of the cart.
Question 16
Two spring-loaded carts are at rest on a low-friction track. The spring is released, pushing the carts away from each other. Three situations are shown. Identify any situation that violates the law of momentum conservation. NOTE: The bricks on top of the carts have the same mass as the cart. The arrows represent the velocity of the cart.
Question 17
Two spring-loaded carts are at rest on a low-friction track. The spring is released, pushing the carts away from each other. Three situations are shown. Identify any situation that violates the law of momentum conservation. NOTE: The bricks on top of the carts have the same mass as the cart. The arrows represent the velocity of the cart.
Question 18
Two spring-loaded carts are at rest on a low-friction track. The spring is released, pushing the carts away from each other. Three situations are shown. Identify any situation that violates the law of momentum conservation. NOTE: The bricks on top of the carts have the same mass as the cart. The arrows represent the velocity of the cart.