Kinematics Word Problems

A car travels at a constant speed of 60 km/h. How far will it travel in 3 hours?

• 180 km

• 90 km

• 200 km

• 120 km

Answer explanation

The car travels at a constant speed of 60 km/h for 3 hours, so the distance traveled is 60 km/h * 3 h = 180 km. Therefore, the correct answer is 180 km.

An object is dropped from a height of 100 meters. How long will it take to reach the ground?

• 6.98 seconds

• 3.75 seconds

• 4.51 seconds

• 5.25 seconds

Answer explanation

The object will take 4.51 seconds to reach the ground, calculated using the formula t = sqrt(2h/g) where h is the height (100m) and g is the acceleration due to gravity (9.81 m/s^2).

A train accelerates from rest at 2 m/s^2 for 10 seconds. What is its final velocity?

• 15 m/s

• 25 m/s

• 30 m/s

• 20 m/s

Answer explanation

The final velocity can be calculated using the formula: final velocity = initial velocity + (acceleration * time). Plugging in the values, final velocity = 0 + (2 * 10) = 20 m/s. Therefore, the correct answer is 20 m/s.

A ball is thrown vertically upwards with an initial velocity of 20 m/s. How high will it go?

• 18.32 meters

• 15.75 meters

• 22.89 meters

• 20.41 meters

Answer explanation

The ball will reach a height of 20.41 meters because the formula to calculate the maximum height of a vertically thrown object is h = (v^2) / (2g), where v is the initial velocity (20 m/s) and g is the acceleration due to gravity (9.81 m/s^2).

A cyclist travels at a speed of 10 m/s for 2 minutes. How far does the cyclist travel?

• 800 meters

• 1000 meters

• 1200 meters

• 1500 meters

Answer explanation

The cyclist travels at a speed of 10 m/s for 2 minutes, which is 10 * 60 * 2 = 1200 meters. Therefore, the correct answer is 1200 meters.

A plane flies at a constant speed of 500 km/h for 4 hours. What is the total distance traveled?

• 2000 km

• 1500 km

• 1000 km

• 3000 km

Answer explanation

The total distance traveled is calculated by multiplying the speed (500 km/h) by the time (4 hours), resulting in 2000 km. Therefore, the correct answer is 2000 km.

A stone is thrown horizontally with a speed of 15 m/s from a cliff 20 meters high. How far from the base of the cliff does the stone land?

• The stone lands 35.2 meters from the base of the cliff.

• The stone lands 40.5 meters from the base of the cliff.

• The stone lands 25.8 meters from the base of the cliff.

• The stone lands 30.6 meters from the base of the cliff.

Answer explanation

The stone lands 30.6 meters from the base of the cliff because the horizontal distance traveled can be calculated using the formula: distance = speed * time. Time can be found using the formula: time = sqrt(2 * height / g), where g is the acceleration due to gravity. Substituting the values, we get time = sqrt(2 * 20 / 9.8) = 2.02 seconds. Therefore, distance = 15 * 2.02 = 30.6 meters.

A car decelerates from 30 m/s to rest in 5 seconds. What is the acceleration?

• -6 m/s^2

• -5 m/s^2

• -10 m/s^2

• -3 m/s^2

Answer explanation

The acceleration can be calculated using the formula: acceleration = (final velocity - initial velocity) / time. Substituting the values, we get acceleration = (0 m/s - 30 m/s) / 5 s = -6 m/s^2. Therefore, the correct answer is -6 m/s^2.

A rocket accelerates from 0 to 200 m/s in 10 seconds. What is the average acceleration?

• 20 m/s^2

• 30 m/s^2

• 50 m/s^2

• 15 m/s^2

Answer explanation

Average acceleration is change in velocity divided by time. (200 m/s - 0 m/s) / 10 s = 20 m/s^2. Therefore, the correct answer is 20 m/s^2.

A sprinter accelerates from rest at 3 m/s^2 for 5 seconds. What is the final velocity?

• 10 m/s

• 20 m/s

• 25 m/s

• 15 m/s

Answer explanation

The final velocity can be calculated using the formula: final velocity = initial velocity + (acceleration * time). Plugging in the values, final velocity = 0 + (3 m/s^2 * 5s) = 15 m/s. Therefore, the correct answer is 15 m/s.