Một chất điểm khối lượng m=200g chuyển động chậm dần với vận tốc biến đổi theo qui luật
v=30 – 0,4t2 (SI). Lực hãm tác dụng vào chất điểm
lúc t = 5 giây là
A. 8 N B. 0,8 N C. 4 N D. 0,4 N

For a particular reaction, ? h = -144.6 kj and ? s = -301.2 j/k. calculate ? g for this reaction at 298 k.

The discovery that the universe appears to be expanding led to a widely accepted theory called a.) the big bang theory b.) the doppler effect c.) hubble’s law d.) solar nebular theory e.) the seyfert theory

An alligator swims to the left with a constant velocity of 5 \,\dfrac{\text{m}}{\text s}5 s m ? 5, space, start fraction, m, divided by, s, end fraction. when the alligator sees a bird straight ahead, the alligator speeds up with a constant acceleration of 3 \,\dfrac{\text {m}}{\text s^2}3 s 2 m ? 3, space, start fraction, m, divided by, s, start superscript, 2, end superscript, end fraction leftward until it reaches a final velocity of 35 \,\dfrac{\text {m}}{\text s}35 s m ? 35, space, start fraction, m, divided by, s, end fraction leftward. how many seconds does it take the alligator to speed up from 5 \,\dfrac{\text {m}}{\text s}5 s m ? 5, space, start fraction, m, divided by, s, end fraction to 35 \,\dfrac{\text {m}}{\text s}35 s m ? 35, space, start fraction, m, divided by, s, end fraction?