A stone of 1 kg is thrown with a velocity of 20 m s-1 across the frozen surface of a lake and comes to rest after travelling a distance of 50 m

Monjur Alahi

A stone of 1 kg is thrown with a velocity of 20 m s-1 across the frozen surface of a lake and comes to rest after travelling a distance of 50 m. What is the force of friction between the stone and the ice?


0 like 0 dislike
1 views
Share with your friends

1 Answers

Salim Ahmed Kawsar

Call

Initial velocity of the stone, u = 20 m/s 

Final velocity of the stone, v = 0 m/s 

Distance covered by the stone, s = 50 m 

According to the third equation of motion: 

v 2 = u 2 + 2as 

Where, 

Acceleration, a 

(0)2 = (20)2 + 2 × a × 50 

a = – 4 m/s2 

The negative sign indicates that acceleration is acting against the motion of the stone. 

Mass of the stone, m = 1 kg 

From Newton's second law of motion: 

Force, F = Mass x Acceleration 

F= ma 

F= 1 × (– 4) = – 4 N 

Hence, the force of friction between the stone and the ice is – 4 N.

0 like 0 dislike
1 views
Talk Doctor Online in Bissoy App
A coin is tossed. If the outcome is a head, a die is thrown. If the die shows up an even number, the die is thrown again.

When a coin is tossed, the possible outcomes are head (H) and tail (T). When a die is thrown, the possible outcomes are 1, 2, 3, 4, 5, or 6. Thus, the...

1 Answers 1 views
A stone is thrown vertically upward with an initial velocity of 40 m/s

According to the equation of motion under gravity v2 − u2 = 2gs  Where,  u = Initial velocity of the stone = 40 m/s  v = Final velocity of the stone = 0...

1 Answers 1 views
On the earth, a stone is thrown from a height in a direction parallel to the earth’s surface

Both stones will take the same time to reach the ground because the two stones fall from the same height.

1 Answers 1 views
In a lake contaminated with pesticides, which one of the following organism living in the lake will contain the maximum amount of pesticide?

The concentration of pesticide will increase with the rise of trophic level in the food chain. Phytoplankton -----> Zooplankton ---> Small fish -----> Big fish (maximum pesticide)  Therefore, big fishes will have maximum...

1 Answers 1 views
Boojho comes across an animal having a stream-lined and slippery body. What is the habitat of the animal?

(a) Water,  Answer is correct

1 Answers 1 views
A die is thrown repeatedly until a six comes up. What is the sample space for this experiment

In this experiment, six may come up on the first throw, the second throw, the third throw and so on till six is obtained. Hence, the sample space of this experiment...

1 Answers 1 views
A person travelling on a straight line moves with a uniform velocity v_1 for some time and with uniform velocity v_2 for the next equal time.

(a) v = (v1 + v2)/2. Explanation:  Let t be the time related to each velocity. Total distance travelled =v1t+v2t. Total time taken=2t. Hence average velocity = v1t+v2t/2t  =(v1+v2)/2.

1 Answers 1 views
A stone is released from an elevator going up with an acceleration a. The acceleration of the stone after the release is

(d) g downward Explanation: Gravity is the only force acting on the stone when it is released. And, we know that gravity is always in the downward direction.

1 Answers 1 views
A person standing near the edge of the top of a building throws two balls A and B. The ball A is thrown vertically upward and B is thrown vertically ,

The correct answer is (c) vA = vB  Explanation: The ball 'A' thrown vertically upward will return back to the initial point with the same thrown speed but its direction will be downwards....

1 Answers 1 views
A person travelling on a straight line moves with a uniform velocity v1 for a distance x and with a uniform velocity v2 for the next equal distance.

(c)  2/v = 1/v1 + 1/v2. Explanation: Time taken during first phase =  x/v1 and during second phase =  x/v2.  Total distance =2x   Total time taken = (x/v1)+(x/v2) = x(1/v1 +1/v2)     Average velocity =Total distance/Total...

1 Answers 27 views
X