Question: motion in a straight line at constant speed is called
[{'answer': 'uniform linear motion', 'provenance': [{'wikipedia_id': '16652317', 'title': 'Linear motion', 'start_paragraph_id': 1, 'start_character': 217, 'end_paragraph_id': 1, 'end_character': 238, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '16652317', 'title': 'Linear motion', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 576, 'bleu_score': 0.8589106880776871, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 6139051777460135042}, 'section': 'Section::::Abstract.'}]}]