Grade 4 Unit 4

Gravity is a force that pulls objects towards each other. It is responsible for keeping objects on the surface of the Earth and for the motion of celestial bodies. This force is always attractive, meaning it pulls objects together rather than pushing them apart. Therefore, the correct answer is "pull".

Based on the information provided in the chart, Magnet H had the greatest magnetic force as it was able to lift the highest number of paperclips compared to the other magnets (F, G, and J).

The correct answer is A pencil falling to the floor. This is an example of the effect of gravity on an object because gravity is the force that pulls objects towards the center of the Earth. In this case, the pencil is being pulled downwards by gravity, causing it to fall towards the floor.

Friction is the force that acts opposite to motion and slows things down. When two surfaces come into contact, microscopic irregularities create resistance, causing objects to experience friction. This force opposes the direction of motion, making it harder for objects to move. Gravity is a force that attracts objects towards each other, magnetism is the force of attraction or repulsion between magnets or magnetic materials, and speed is a measure of how fast an object is moving.

The students are changing the variable of friction. They are testing different surfaces to determine which one would provide the least amount of friction and therefore be the easiest to ride their bicycle across.

Car B traveled farther than Car A because smooth wood has less friction than sandpaper.

If the white arrow represents a downward force that is greater than the mass of the box, the box will most likely move up. This is because the force applied by the arrow is greater than the force of gravity acting on the box, causing it to move in the opposite direction of the force.

The balance and meter stick would be most useful in testing how the mass of an object can affect the distance it moves after being pushed. The balance can be used to measure the mass of the object accurately, while the meter stick can be used to measure the distance the object moves after being pushed. By varying the mass of the object and measuring the corresponding distance it moves, one can analyze the relationship between mass and distance and determine how they are related.

Repeating an investigation multiple times is a good practice because it helps to obtain more reliable information. By conducting the test multiple times, students can identify any inconsistencies or errors that may have occurred during a single trial. This repetition allows them to gather a larger sample size, reducing the impact of any outliers or random errors. It also helps to validate the results and ensure that they are consistent and reproducible. Overall, repeating an investigation increases the accuracy and reliability of the information obtained.

Scientists were trying to work against the pull of gravity when developing the space shuttle. Gravity is a force that pulls objects towards the center of the Earth. In order to launch the space shuttle into space, scientists needed to overcome this force by using powerful rocket boosters to push the shuttle away from Earth.