Depends what car it is.
Most cars can stop from 60 mph in about 100 feet or so. If the relationship is linear then a car should stop from 30 mph in about 50 feet.
That means that every hour, you move 30 miles. The actual distance travelled depends on the time travelled: d = st (distance = speed x time).
24 minutes.
1 hour and 30 minutes.
Depends what car it is.
time = distance / speed = 30 miles / (6 miles/hour) = 5 hours.
2,700 miles.
There isn't a direct linear relationship between speed and stopping distance with locked brakes. The stopping distance increases exponentially with speed due to factors like increased kinetic energy and reduced tire grip at higher speeds. It's not accurate to calculate the stopping distance at 90 mph just by extrapolating from the data given for 30 mph. Specialized calculations or tests are needed to determine the stopping distance at 90 mph.
Stopping distance at 30mph = 23m
Most cars can stop from 60 mph in about 100 feet or so. If the relationship is linear then a car should stop from 30 mph in about 50 feet.
That means that every hour, you move 30 miles. The actual distance travelled depends on the time travelled: d = st (distance = speed x time).
You can go 7.5 miles driving at 15 miles per hour for 30 minutes. This is because 30 minutes is 1/2 of an hour, and 1/2 of 15 miles (the distance you travel in an hour) is 7.5 miles.
24 minutes.
Distance = Speed*Time = 30 miles per hour * 7 minutes = 30 miles per hour * 7/60 hours = 7/2 miles
1 hour and 30 minutes.
Time = Distance/Speed = 30/120 = 0.25 hours.