Answer:
true
Explanation:
An Electromagnet is called as a temporary magnet, because electromagnet is made up of insulated copper wire wrapped around soft iron, which allows current to flow in it and at that moment iron gains it magnetic properties and when the current is switched off, then there will be no flow of current and hence iron loses its magnetic properties.
Hence it works temporarily as long as electric current flows in a conductor and hence known as temporary magnet. .
A tennis ball is hit by a large force so that it goes up into the air and then it comes back straight down because of gravity.
<h3>How object move upward and downward?</h3>
We know that objects move upward due to application of force on it while on the other hand, object comes to the ground because of the attraction of earth which we called gravity.
So we can conclude that a tennis ball is hit by a large force so that it goes up into the air and then it comes back straight down because of gravity.
Learn more about force here: brainly.com/question/12970081
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Answer:
a) -1.25 m/s²
b) 62.5 m
Explanation:
Convert km/h to m/s:
45 km/h × (1000 m/km) × (1 h / 3600 s) = 12.5 m/s
a = Δv / Δt
a = (0 m/s − 12.5 m/s) / 10 s
a = -1.25 m/s²
Δx = ½ (v + v₀) t
Δx = ½ (0 m/s + 12.5 m/s) (10 s)
Δx = 62.5 m
The acceleration of the wagon along the ground is 3.6 m/s².
To solve the problem above, we need to use the formula of acceleration as related to force and mass.
Acceleration: This can be defined as the rate of change of velocity.
⇒ Formula:
- Fcos∅ = ma................. Equation 1
⇒ Where:
- F = Force
- ∅ = angle above the horizontal
- m = mass of the wagon
- a = acceleration of the wagon
⇒ make a the subject of equation 1
- a = Fcos∅/m..................... Equation 2
From the question,
⇒ Given:
⇒ Substitute these values into equation 2
- a = 44(cos35°)/10
- a = 44(0.8191)/10
- a = 3.6 m/s²
Hence, The acceleration of the wagon along the ground is 3.6 m/s²
Learn more about acceleration here: brainly.com/question/9408577
