How to Solve Basic Physics Problems Correctly?

AI Thread Summary
To solve basic physics problems, key calculations involve understanding displacement, velocity, and acceleration. For example, to find time of travel, divide displacement by velocity, as shown in the car problem where 150 km at 50 km/h results in 3.0 hours. When calculating required speed for a journey, first determine distance covered in the initial time, then divide the remaining distance by the remaining time. Acceleration is found by subtracting initial velocity from final velocity and dividing by time, as demonstrated in the car acceleration example. Lastly, calculating collision force involves converting speed to m/s, finding acceleration, and applying the impulse formula.
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8. If the displacement of a car was 150 km [E] and the velocity was 50.0 km/h [E], what was
the time of travel?
A. 100 h [E]
B. 3.0 h
C. 100 h
D. 3.0 h [E]

(I divided 150 by 50)

9. The airport is 60.0 km away and you have 1.00 h to get there. If your speed for the first
40.0 minutes is 48.0 km/h, how fast must you travel in the remaining 20 minutes to get
there within the time?
A. 48.0 km/h
B. 84.0 km/h
C. 90.0 km/h
D. 180 km/h
( for this I converted the times to hours then I found the distance it traveled first then I subtracted it from the whole distance it has to travel then I divided the amount it still had to travel by the remaining time)

10. If the velocity of a car is 16 m/s and it travels for a time of 6.0 s, what is the
displacement? Express the displacement correctly.
A. 96 m
B. 10 m
C. 96 m
D. 10 m/s
(for this I multiplied the velocity by the time it traveled and inferred that it doesn't include direction)

11. A racoon travels from point A to point B in 11 s. If the racoon was displaced 55 m ,
what was its velocity? Express the number correctly.
A. 5.0 m/s
B. 5.0 m/s
C. 44 m/s
D. 66 m/s
(for this I divided the displacement by the time)

12. A car driver speeds up from 5.00 m/s [E] to 15.0 m/s [E] in 4.00 s. Determine the car’s
acceleration.
A. 40.0 m/s2 [E]
B. 40.0 m/s [E]
C. 2.50 m/s2 [E]
D. 2.50 m/s [E]
(for this I subtracted the final velocity from the initial velocity and the divided this value from the time)

13. An 1800 kg Volkswagen traveling at 60.0 km/h impacts into a concrete barrier and stops
in 0.420 s. The magnitude of the collision force on the automobile is
A. 2.57 x 105 N
B. 7.14 x 104 N
C. 1.26 x 104 N
D. 1.08 x 105 N
(for this I first converted the speed to m/s then divided this by the time to get acceleration then I multiplied this by 1800 Kg is this the correct way to do it do i calculate the acceleration by dividing the given velocityby the time or is there another way to do it)
 
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All of the answers are correct

#13 :

impulse = mass*speed
speed = 16.67 m/s
mass= 1800 kg

force of collision = impulse/time
 
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