The same force is used to accelerate a small car and a monster car. Whal will be different about their motions? Explain your answer.
The acceleration of the monster car will be smaller due to its greater mass (Newton's second law)
Oops!
Check
Okay!
Check
heart
Other team wins 5 points!
Oops!
rocket
Go to first place!
Okay!
rocket
Go to first place!
Okay!
thief
Give points!
5
10
15
20
25
15
Explain why Formula 1 racing cars have low masses.
Because, the lower the mass the higher the acceleration (Newton's second law).
Oops!
Check
Okay!
Check
15
Explain why when you are swimming you have to push water backwards so that you can move forwards.
When you push the water backwards, the water exerts on you a reaction force that is equal in magnitude and opposite in direction (Newton's third law).
Oops!
Check
Okay!
Check
15
Explain why a passenger, who is standing, might lose his balance if a train accelerates quickly out of a station.
Because the passenger is static, and he tends to remain static as no force acts on him (NewtonÂīs first law).
Oops!
Check
Okay!
Check
15
Explain why a gun recoils backwards when fired.
The gun exerts a force on the bullet in the forward direction. The bullet also exerts an equal and opposite force on the gun (Newton's third law).
Oops!
Check
Okay!
Check
15
Does rubber in the extension-Ioad graph obey Hooke's law? Explain.
No, because Hooke's law says that the deformation of an elastic material is proportional to the force applied to it and thus we would get a linear graph.
Oops!
Check
Okay!
Check
15
What happens to the moticn of an object when the forces on it are balanced?
If it is static, it will stay static. If it is in motion, it will continue to move in the same direction and at the same speed. (Newton's first law).
Oops!
Check
Okay!
Check
boom
Lose 50 points!
Oops!
magnet
Take 25 points!
Okay!
gift
Win 25 points!
Okay!
thief
Give points!
5
10
15
20
25
thief
Give points!
5
10
15
20
25
fairy
Take points!
5
10
15
20
25
rocket
Go to first place!
Okay!
baam
Lose 25 points!
Oops!
15
Determine the reaction force involved when a ball is hit with a racquet with a force of 100 N west.
The force of the ball pushing back against the strings of the racquet (Newton's third law).
Oops!
Check
Okay!
Check
15
Explain why oil tankers (which have masses of about half a million tons) take about 20 minutes to stop moving when their engines are turned off.
A more massive object has a greater tendency to resist changes in its state of motion. The higher the mass, the lower the acceleration (Newton's second law).
Oops!
Check
Okay!
Check
15
when a horse pulls on a cart, the cart pulls back with an equal force on the horse. If, in fact, the cart pulls back on the horse as hard as the horse pulls forward on the cart, how is it possible for the horse to move the cart?
Because this is not the force from which motion comes from. Motion comes from the horse pushing the road and the road pushing the horse forward.
Oops!
Check
Okay!
Check
15
Explain why you cannot walk easily on icy ground.
When we walk, we push the road backwards. Due to friction, the road pushes us forwards with an equal and opposite force (Newton's third law).
Oops!
Check
Okay!
Check
15
On which factors force of friction depends?
The roughness of the contact surface and the weight of the object that moves.
